In assembling the informa¬ tion contained in this bulletin, we have consulted the follow¬ ing authorities; United States Bureau of Standards Test Data. Transmission of Heat Through Building Materials. Bulletin No. 3, Engineering Dept., University of Minnesota, by Prof. F. B. Rowley. Mechanical Equipment of Build¬ ings; Professors Willard & Harding, University of Illinois. Transmission of Insulating M.vte- RiALS. Data compiled by American Society of Refrigerating Engineers. Investigation of Methods for Testing Heat Insulators, Bul¬ letin No. 33, Engineering Depart¬ ment, Pennsylvania State College, by Professor E. F. Grundhofer. Test Data of Armour Institute, Chicago, by Professor J. C. Peebles. The Acoustics of Buildings, by Prof. F.R. Watson, University of Illinois. The insulation of this home was a straight Flax-li-nnin specification. Fac- j IVAN DISK and CLAIR W. DITCHY tors for heat losses, radiation requirements Architects - Detroit, Michigan and fuel consumption are given on pages 26 and 27 of this book. Tla^c-li-nmn THE CORRECT BUILDING INSULATION AND SOUND CONTROL MATERIAL * A treatise on Insulation for build¬ ings, compiled for ready reference for Architects and Engineers. Copyright, 1927 FLAX-LI-NUM INSULATING COMPANY ST. PAUL, MINN. PRINTED IN U. S. A. TABLE O F CONTENTS Contents Flax-li-imiii. Its Origin, Development and Uses - -- -- -- -- -- Page 5 Wli at Is a Correct Insulation? - -- -- -- -- -- -- -- -- -- -- 5 The Correct lUiilding Insnlation - -- -- -- -- -- -- -- -- -- - (> What Flax-li-niini Is - -- -- -- -- -- -- -- -- -- -- -- -- (> The Flax-li-nnm Insulating Method - -- -- -- -- -- -- -- -- -- 7 Heat Transfer and Its Measurement - -- -- -- -- -- -- -- -- - 8 II eat Losses From Buildings - -- -- -- -- -- -- -- -- -- -- - 9 F. fleet of Surface Resistances on Efficiency - -- -- -- -- -- -- -- -l() Heat Loss Through House Roofs - -- -- -- -- -- -- -- -- -- -10 The Determination of Transmission Co-efficients - -- -- -- -- -- -- H Formulae For Standard Walls and Roofs - -- -- -- -- -- -- -- - 13 Standard Wall and Roof Sections - -- -- -- -- -- -- -- -- -- - 14 Determining Net Fuel Savings on Actual Houses - -- -- -- -- -- --18 Heat Losses on Bungalow Type Houses - H eat Losses on Larger Type Houses - -- -- -- -- -- -- -- -- - Suggestions for Specifying Heat Insulation - -- -- -- -- -- -- -- - List of Flax-li-num Specifications - -- -- -- -- -- -- -- -- -- -29 Thermal Insulation Specifications - -- -- -- -- -- -- -- -- -- -31 Flax-li-num Sound Control - -- -- -- -- -- -- -- -- -- -- --38 Sound Control Specifications - -- -- -- -- -- -- -- -- -- -- -4i Industrial Roof Insulation - -- -- -- -- -- -- -- -- -- -- -- 48 Heat Transmission Values for Roofs - 50 Humidity Control Chart and Data - -- -- -- -- -- -- -- -- -- 51 Aj)artment House Roof Data - -- -- -- -- -- -- -- -- -- -- - 50 Radiation Reciuirements and Fuel Losses on Industrial Roofs, of Concrete, Wood and Steel - -- -- -- -- -- -- -- -- -- -- -- -- -- -- Roof S]3ecifications - -- -- -- -- -- -- -- -- -- -- -- -- -55 Flax-li-num Test Data - -- -- -- -- -- -- -- -- -- -- -- - 58 Flax-li-num Stock Sizes - -- -- -- -- .- -- -- -- -- -- -- -59 Flax-li-num Radiation Conij)utation Chart -------- Back Inside Cover HEAT INSULATION FOR HOUSES Plax-ll-num F EVERY building in the United States today were insulated there would be conserved each year at least 30 % of the Nation’s annual coal hill. It has been conservatively estimated that there is wasted in fuel every year in the United States the enormous sum of $ 450 , 000,000 because of poor, or un¬ scientific construction of house walls and roof. This tremendous National waste has of late years had the attention of leading engineers and conservationists. Notable among whom were the late Chas. P. Steinmetz, consulting ing huts of thatched grass, and the thicker and engineer of the General Electric Company, and Ex- President Theodore Roosevelt. Dr. Steinmetz in discussing the subject said, “Our present structures are causing annual leakage costs of literally mil¬ lions of dollars’ worth of heat. The house of the future will be scientifically built from the stand¬ point of heating.” Begmning of the Insulation Idea The idea of heat insulation from the standpoint of comfort is a primitive one. People of earlier times endeavored to secure comfort for their places of abode by various methods. Perhaps the most notable of early methods being the “Wattle and Daub” construction of the New England colonists, who filled the open spaces between uprights in their houses with a mixture of straw and mud. Primitive methods are known today, and a degree of comfort is secured bv both the Eskimo and the South Sea Islander by the application of natural insulation principles. In the far north the Eskimo builds his igloo with insulation only—snow blocks which con¬ tain millions of entrapped air cells—and keeps com- fortablv warm with a small seal-oil flame. At the other extreme of temperature the aborigines of the tropics found that they could enjoy a degree of comfortable relief from the burning sun, by build- firmer the thatch, the cooler was the interior. These are applications of natural insulation principles. Modeini Construction and Insulation As building methods developed, new fuel sup¬ plies opened up, and more efficient methods of con¬ suming fuel came into general use, the tendency of home construction has been toward units that have been increasingly better protection against rain, snow and wind, but not against the passage of heat. As fuel costs advanced, insulation again began to force itself on the consciousness of the building public, so that back-plaster came into vogue and remained common practice until the early part of the present century, when serious attention was first really given to a search for and development of a really efficient insulating material. What Is a Correct Building Insulation^ A correct and efficient building insulation must possess the following characteristics: First —it must be a far better heat-stop than any of the corn- building materials. Second —It should be mon made of permanent raw materials and in perma¬ nent form. Third —It should be easy to handle and install, since the application is as important as the material. Fourth —Insulation should make 4 6 Heat Insulation for Houses possible fuel savings that will represent a sizable re- Flax-li-nnm very definitely brings the following turn on the investment. economies: The Correct Building Insulation Flax-li-nnm has been called the correct building insulation because it meets fully each and every one of the above recinirements. Fir.^t —Flax-li-nnm is an efficient non-conductor of heat when compared with familiar building materials. One inch of Flax- li-nnm stops as much heat as sixteen inches of brick, or twenty-seven inches of concrete. 1 of Flax'li -ntun -16 of Brick andi Mortar or s27of SoliJ Concroto Showing the relative heat stopping qualities of common building materials. Second —Flax-li-nnm is made from nature’s toughest and longest lived vegetable fibre. It is impervious to decay and in its semi-rigid form it is guaranteed to remain in place at full efficiency as long as a building stands. Third —Flax-li-nnm is decidedly easy to handle and install. It comes in flanged sheets ready to apply between studdings on wood construction and in flat sheets for roof and ceiling insulation. It is semi-rigid in form, not subject to breakage, buck¬ ling or warping, and is flexible enough to adapt it¬ self to the shrinkage of construction members and settlement of the building without impairing in any way its efficiency or its application. Fourth —Flax-li-num makes an attractive invest¬ ment. Because it so materially reduces heat losses, it makes j)ossible a reduction in radiation require¬ ments, and this saving offsets a large ])ortion of the original insulation cost. The full cost of Flax-li-num can be regained in fuel savings within three years and thereafter, as long as the building stands, the an¬ nual saving comes to the owner as an excellent dividend on his Flax-li-num investment. 1 . Economv of Fuel. _t_ *2. Economv in Radiation. __ 3 . Piconomv effected bv Health Conditions. %■ Flax-li-num Introduced in 1909 Flax-li-num was developed by the late Mr. Geb- liard Bohn, pioneer manufacturer and owner of im¬ portant patents covering refrigerators and refrig¬ erator car construction. Beginning in 1909 Flax- li-num was tried and tested in these vigorous fields. It was installed in thousands of refrigerator cars, where constant vibration and racking test the dur¬ ability of the insulating material to the utmost. Since that year the transportation of fruits, meats, and perishable merchandise has been successfully carried on bv American railroads in thousands of F'lax-li-num insulated refrigerator cars. That Flax-li-num has met fully the exacting re- (juirements of this rigid service is proven by the fact that today Flax-li-num is the Standard in¬ sulation on many of America’s largest refrigerator transportation lines. Flax-li-num finds extensive use in the insulation of high class domestic and market refrigerators, iceless ice cream shipping containers and kindred products. What Flax-li-num Is Flax-li-num is a semi-rigid board, felted from the long tough fibres of the Flax plant. Flax is a natural insulator. Miscroscopic inspection reveals that the stalks are made up of a multitude of tiny air cells, each separated from the other by thin tis¬ sue walls. The long fibres interlacing in the sheet create additional cells, and the multiplicity of these minute air cells accounts for the efficiency of Flax- li-num as a resistant to the passage of heat. No artificial binder is required to make a strong build¬ ing material from the Flax. The interlacing of the long fibrous material giving the necessary binding ciualities to hold together the “felted” sheet. Heat Insulation for Houses 7 Tlie Flax plant does not rot, as do the straws from cereal grains, such as wheat and rye. For this reason the Flax straw on farms in flax growing countries was burned since it could serve no useful purpose on the farm. It is this inherent quality of the flax fibre that gives to Flax-li-num its long life and the assurance that the insulation will last as long as the building stands. In the process of man¬ ufacture Flax-li-num is chemically treated to re¬ move the natural oils and gums from the fibre. This chemical treatment renders Flax-li-num ver¬ min and rodent proof. Not a Substitute or Dual-Purpose Matet'ial Flax-li-num today occupies the same ground as when it was introduced. It gives the utmost in in¬ sulating efficiency, combined with rugged durabil¬ ity, ease of application and guaranteed long life It is guaranteed by the makers never to fall down or become displaced in the walls of any building. Because it is not a rigid board it cannot warp, break or crack, either when buildings settle or be¬ cause of the expansion and contraction of its own fibres. It does not substitute for the accepted wood or metal lath, nor for sheathing or any other part of the construction. Consequently its makers are not forced to cater to dual uses, which weaken the vital use—heat insulation. The fact that Flax-li- num to date lines more houses than all other insu¬ lations combined, that it is the standard insulation used in American Railway refrigerator cars, and that it is standard equipment on the highest grade refrigerators, is conclusive proof of the soundness of Flax-li-num as a product, and of the correctness of its recommended application. The Flax-li-num hisidating Method At the same time that Flax-li-num was being de¬ veloped as a material, there was being developed with it an insulation method. The material and method are closely allied, and this brings us to a consideration of the various Flax-li-num applica¬ tions in walls and roofs of frame, brick, hollow tile or veneer construction. The Flax-li-num method calls for the application of flanged material midway between the inner and outer portions of frame walls. Certain of our specifications for brick and tile, which are fully covered in this volume, call for the use of fiat sheets, but each application has been so designed that the owner will receive the full benefit of surface resistances, as described in detail in the chapter on “Heat Losses from Buildings.” The methods of applying insulation, as covered in the accompanying specifications, were all developed by the Flax-li-num Insulating Company and have been standard with them for a period of more than fifteen years. It will be noted that all Flax-li-num specifica¬ tions for ceiling and roof insulation call for one inch of material. Our Engineering Department was the first to recognize that the old rule-of-thumb method of calculating heat losses through roofs was wrong, and that the combined ceiling, attic space and roof should be considered as a compound wall in calcu¬ lating heat losses. We were also the first to recog¬ nize the fact that heat losses through the ceiling and roof were practically double those of side wall losses, and since heat transmission is inversely pro¬ portional to the thickness of the insulating mate¬ rial, we established upon a scientific basis the need for one inch of insulation in ceilings and roofs. Having taken this stand there was a long period when the Flax-li-num Company was the only in¬ sulation manufacturer recognizing this application. It is the purpose of this bulletin to set up definite standards of comfort and economv for walls and t' roofs. To do this each wall is figured according to an approved formula, and assigned its correct heat transmission coefficient. Thus, frame, stucco, brick, hollow tile, or any special construction is re¬ duced, from a comfort and economy standpoint, to the common denominator of a transmission coeffi¬ cient, and comparison readily settles between com¬ peting constructions. Many of the walls listed here have been actually tested with exact scientific ap¬ paratus and results given may be readily proven, either by formula or direct experiment. 8 Heat Insulation for Houses Heat Transfer and Its Measurement HE principles underlying heat transfer are comparatively simple. They involve for the most part only familiar elementary conceptions of matter and energy. Some of them are so elementary that they seem frequently to be overlooked when considering practical problems, which might he greatly simplified by their application. A brief review of known facts governing heat travel is here given, as a reminder of the salient points and their application to the study of Insulating Materials. Heat—a DefiJiitioii Heat lias long been known to be a form of energy and not a substance. Modern theories as to the exact nature of heat conceive it to be a motion or agitation of the molecules of which every body is composed. Every substance contains some heat and to say that a body is “cold” means simply that it contains a relatively small amount of heat (mole¬ cular motion). Measurement of Heat In measuring heat there are two quantities to be considered; the intensity and the amount. A small piece of white-hot metal may not contain as great an amount of heat as a pail of warm water, but the intensity of the heat in the former is much greater. The measurement of intensity or temperature is usually based upon some arbitrary scale such as the Fahrenheit or Centigrade thermometers. The British Thermal Unit Heat must be measured by the effect which it produces upon some substance. The unit of heat used in modern engineering practice is the amount needed to raise the temperature of a pound of water one degree Fahrenheit. This is called the British thermal unit and is denoted by the symbol B. t. u. As this quantity is not exactly the same at all tem¬ peratures it is necessary to specify further a defi¬ nite temperature at which the unit is to be estab¬ lished. The practice of different authorities varies in this regard, but the B. t. u. established by Marks and Davis is becoming generally used. Thus it is defined as “the one hundred and eightieth part of the heat necessary to raise the temperature of one pound of Water from 32 ° to 212° F.” The Transmission of Heat Heat mav be transmitted in three wavs: bv ra- ty V diation, by conduction and by convection. Radiation —Heat is transmitted by radiation by what is supposed to be a motion or vibration of the ether which is believed to pervade all space. Radiant heat follows the same physical laws as radiant light, traveling in straight lines. We may have heat “shadows” just as we have light shadows and the intensity of radiant heat is inversely pro¬ portional to the square of the distance from the source from which it comes. Some substances are transparent to heat rays and others absorb them. Gasses are almost per¬ fectly transparent to radiant heat while substances as Flax-li-num are almost opaque to it. Radiant heat does not affect the medium through which it passes. For example, the atmosphere is not percep¬ tibly warmed by the sun’s radiant heat transmit¬ ted to the earth. Conduction —If one part of a body is at a higher temperature than another part there will be a flow of heat through the body. The transmission of heat is this manner is known as conduction. A familiar example of this phenomenon is the flow of heat along an iron bar, one end of which is heated in a fire. The abilitv of different materials to con- duct heat differs considerably. Metals are the best Heat Insulation for Houses 9 conductors of heat, while such materials as Flax- li-num are very poor conductors. Convection —When a body is in contact with a fluid at a lower temperature, the envelope of fluid surrounding the body becomes heated by conduc¬ tion. As this fluid envelope is heated its density de¬ creases and it is forced to rise, giving place to the colder fluid from below. A continuous current is thus created and maintained over the surface of the body. This process of heat transfer is called con¬ vection. It should be noted that the heat actually leaves the hot bodv bv condnction from its surface I I to the fluid in contact with it. The essential char¬ acteristic of the process of convection is the con¬ tinuous renewal of the fluid layer at the surface of contact. Heat may also be transmitted from a fluid to a solid by convection as well as from a solid to a fluid. An example of this process is the transfer of heat from the warm air of a room to the cold out¬ side walls. The air, upon giving up its heat, in¬ creases in density and falls, giving place to warmer air from above and producing a continuous down¬ ward current. Heat Losses From Buildings HEN the interior of any building is maintained at a temperature higher than that of the outside air there is a continual loss of heat from the building. The functions of a heating system are, first, to raise the tem¬ perature of the interior of the building to the point desired and, second, to maintain this temperature by supplying sufficient heat to replace that lost from the building. The determination of the amount of heat lost from the building under maximum demand is the first step in designing the heating system. Methods of Preventing Heat Losses Before taking up the methods of calculating heat loss it is necessary to consider first the manner in which heat may be lost from a building. Buildings lose heat, first, by a combination of conduction, convection and radiation through the walls and roof; second, by actual air leakage or “infiltration”; third, by ventilation. Windows in¬ crease the loss by radiation and conduction. The character of walls and roof determine the amount of loss through them. It is important to recognize the fact that “tight” construction (painting-in window frames, calk¬ ing, lining houses with paper, etc.) affects only the “infiltration” and cannot cut down the great losses due to the three sources of heat travel. No matter how “tight” a sheet metal shed may be it will al¬ ways l)e frigid in winter and unbearabl,y hot in the summer months. There are several practical methods of stopping heat losses. The thermos bottle makes use of two methods, one to prevent transmission by radiation and the other to prevent transmission by convec¬ tion. Radiation has been stopped by silvering the inner surfaces of the bottle so as to reflect the radiant rays. Convection has been stopped by creating a vacuum between the inner and outer bottles. The only method of heat travel not fully stopped by this construction is conduction. There is a slight amount of conduction through the glass at the stopper. Obviously these methods cannot be used in buildings. The method best adapted to buildings is that of forming tiny air cells in the tex¬ ture of a material and incorporating this material into the walls and roof of the structure. All re¬ frigerators, cooling rooms and railroad refrigerator cars operate by the application of this latter meth- 10 Heat Insulation for Houses 0 (1. Somewhere in the walls and roof they have an “INSULATION,” a material containing these fiui/ air spaces. Note that we have emphasized the word tiny in the foregoing paragraph. The large air chambers commonly found in ordinary frame walls, as well as in walls of hollow tile or similar constructions, are not insulation. Air itself is not an insulator. In the best of construction there will always be some circulation of air, and where air circulates there is a transfer of heat. By tiny air cells we mean minute chambers such as contained within the texture of Flax-li-num. Such cells retard the transmission of heat because there is no circula¬ tion of air from one to the other. Surface Resistances Air spaces do affect heat flow in another way, as shown by the diagrams (1 to 3 on page 12). Heat encounters a resistance as it enters and as it leaves an}^ substance. Thus every air space in a wall or roof adds two “surface resistances” to the total. The “surface resistances” of materials differ widel 3 y and thev must be taken into consideration when building. Wh ere the insulation divides the air space in a wall there are produced two surface resistances more than though the same insulation were plac¬ ed against the sheathing or against the plaster. The transmission of the re¬ sulting wall is therefore lower. Thus we explain the reason behind the Flax-li- num s])ecifications No. 4-A and 13-A (pages 31 and 33) which show Flax-li-num dividing the air space between the studding and separated from both plas¬ ter and sheathing in the wall. These specifications, beside their ])ractical features of space saving and economical installation, allow Flax-li-num to func¬ tion at its maximum efhciency bj^ taking advantage of the full surface effects of each member of the wall. This is a utilization of natural laws securing an added benefit. It is a mistake to appl\" heat insulation so tliat these surface effects are lost. To plaster directh" on insulation causes the loss of two surface drops; to apph' insulation over sheathing on the outside and cover with siding also causes the loss of two surface drops. Flax-li-num specifications are designed to produce maximum efficiency on the job. Heat Lost Through Roofs The same formula used to determine heat losses through walls applies to house roofs. The roof construction, as well as that of the top stor^- ceil¬ ing, affects the heat flow and should be considered. For \"ears the popular method of determining this loss was to assume an average winter temperature in the attic or loft, and then consider onlv the transmission from the upstairs rooms to the attic. This attic temperature, for instance was often taken at 40 degrees, where the average temperature outside was being taken many degrees lower. The fact that there was a constant heat loss from the attic which varied with the construction of the roof above it was entirelj^ overlooked. Heat passed from upstairs rooms into the attic, and from the attic to the out-of-doors. The attic forms an open space which adds two surface re¬ sistances to the total heat resistance of the roof and ceiling combination. Considering this combina¬ tion as a compound wall eliminates an old error, and brings computed heat losses nearer the actual. This method is followed b}^ Professor Frank B. Rowley in his Bulletin, “Transmission of Heat Through Building Materialsf'' published October 26, 1923, b}^ the University of Mi nnesota. The 6 formulae given on page 13 accurately gauge all heat losses that occur b^- conduction in straight lines through the ceiling and roof. They are correct without adjustment so long as there is no variation in construction at the eave line. How¬ ever, where the attic floor is used, as in ceilings A, B, E and F, (page 17) a very sizable heat loss occurs from the ceiling into the attic which does not go through this floor, but travels around it b}^ con- Heat Insulation for Houses 11 vection, and up through the open spaces between tlie rafters, which are not as a rule covered by the attic floor. The illustration, Figure 1, shows the manner of this heat loss. In computing the heat loss from ceilings where this construction is in use let us assume the heat resistive qualities of the floor (not any other part of the roof and ceiling combination) as cut in two for a distance of six feet out from the walls. The formula for this O-foot strip, thus, becomes: ] K -- 1 1.125 1 1 .75 1 1 .75 1 — +-H-H-+ — + — + — + — + — 1.2 1.2 1.1 1.1 1.2 1.1 1.3 8.3 1.3 2 1 or K =-= .220 1.511 The heat loss from the roof of the house shown on page 19 is computed on this basis. The Determination of Transmission Coefficients F HOUSE walls and roofs were made up of solid masses of a single ma¬ terial the heat resistance of any wall would be a simple problem of addition. Knowing the resistance coefficient of a given unit thick¬ ness we could add and subtract to obtain the result for a wall or roof as specified. Walls, however, are made up of layers of different materials, each with a different transmission coefficient and are further complicated by air spaces like those commonlv found in frame and tile construction. Some basic formula is necessary to enable us to arrive at the correct heat transmission of any wall or roof. This formula must be theoretically sound, and must check with actual tests in the laboratories of reliable experimental engineers; as well as with observations on actual jobs. The Formula of Willard a7id Lichty The formula universally used by architects and engineers, is that of Messrs. Willard and Liciity, as published in University of Illinois Bulletin No. 102, and as covered in Harding and Willard’s handbook ’‘'Mechanical Equipment of Buildings." No space is available here for the proof of this for¬ mula. Full explanation of its origin and deriva¬ tion is contained in the publications above men¬ tioned. It has been accepted and successfully applied by heating engineers for a period of years, and experimental tests upon wall sections check accurately with the results computed from the formula. Development of the formula for simple and com¬ pound walls is shown in the three diagrams on the following page. The key is as follows: 12 Heat Insulation for Houses K =^heat transmission coefficient of wall desired in 15. t. u. per sq. ft. per dg. F. per hr. C -conductivity coefficient of material making up wall (per inch of thickness) in B. t. u. per sq. ft. per degree F. per hr. Si —inside surface coefficient of material making up wall in B. t. u. per sq. ft. per dg. F. per hr. So - outside surface coefficient of material making up wall in B. t. u. per sq. ft. per dg. F. per hr. X -thickness in inches. The factors, So, Si, S2, S3, S4, and Cl, C2, Cs, etc., are known from tabulations of tests and experi¬ ments. The figure (.210) gives us the amount of heat in B. t. u.’s transmitted through a square foot of the Brick Veneer wall shown below for every degree difference between the outside and inside tempera¬ ture for every hour of time. FIG. 1 FIG. 2 Heat Transmission Thru Simple Wall Heat Transmission Thru Wall of More Than One Material, But Without Air Spaces 1 K =- 1 X 1 - -|--j- So C Si FIG. 3 Heat Transmission Thru Wall Made Up of Various Materials and Containing Air Spaces 1 X 1 X X 1 1 X 1 -1- \ -H-1-^-1-1-1- So Cl S 2 C 2 Cs S 3 Si Cl Si See wall A-2—opposite page A group of typical small homes showing the snow melted from the roofs due to lack of roof insulation. 1 " of Flax-li-num would have prevented the heat leaking through the roofs and made a substantial reduction in fuel require¬ ments on each of these homes. Note that the snow remains on the unheated porches. Heat Insulation for Houses 13 Transmission Coefficients of Walls Stucco Walls—^See Page 14 Wall A-1 1 1 K= --=-= .242 1 .75 1 .02 75 1 1 .75 1 4.137 -1-1-1-1-1-1-1-1- 3.9 8,3 1 3 4 1 2 1 4 1 3 8.3 1 3 Wall B-1 1 1 K= - ■ --=-=.14(i 1 75 1 .02 .75 1 1 1 .75 1 G.S42 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 3 9 8 3 1.3 .4 1.2 1.4 .37 1.3 8.3 1.3 Wall C-l 1 1 1 .75 .5 1 1 1 75 1 3.490 -1-1-1- \ -1-1-1- 3.9 8.3 1 2 1.3 1 4 1.3 8.3 1.3 Brick Walls—Continued Wall D-2 1 K=- 14 1111 - 1 - 1 - 1 - 1 - 1 - 4.2 5 .99 .99 1.3 .31 Wall E-2 1 1 13 1 1 .75 1 - 1 - 1 - 1 - 1 - 1 - 4.2 5 1 3 1 3 8.3 1 3 Wall F-2 1 K=- 1 13 1 1 - 1 - 1 - 1 - 4.2 5 1.3 31 1 - =141 7.058 1 -=.191 5 238 1 -= .14(1 (i.83,S Wall D-1 1 1 K=-=-= .161 1 .75 .5 1 1 1 1 .75 1 6.220 -1-1-1-]-1-1-1-1- 3 9 8.3 1 2 1.3 1 4 .37 1.3 8.3 1.3 Wall E-1 1 1 K= -=-= .357 1 1.25 1 1 .75 1 2.805 -1-1-1-1-1- 3 9 8.3 1 3 1.3 8 3 1.3 Wall F-1 1 1 K= -=- =181 1 1.25 1 1 1 .75 1 5.515 — +-+ — + — + — + — + — 3.9 8.3 1.3 .37 1.3 8.3 1.3 Brick Walls—See Page 15 Wall A-2 1 1 K=-=-= .210 1 4 1 .02 .75 1 1 ,75 1 4.769 -1-1-1-1-1-1-]-1- 4.2 5 1 4 4 1.2 1.4 1.3 8.3 1 3 Wall B-2 1 1 K=-=-= ,133 1 4 1 .02 .75 1 1 1 .75 1 7.499 -1-1-1-1-1-1-1-1-1- 4.2 5 1.4 4 1 2 1.4 .37 1.3 8.3 1 3 Frame Walls—See Page 16 Wall A-3 1 1 1 1.125 .02 1 1 .75 1 -1-1 -. -1-1-1-1-1- 4 2 1.4 1.2 ,4 1 4 1 3 8.3 13 2 Wall B-3 1 K=--- 1 1 1.125 .02 1 1 1 .75 1 -1-1-1-1-1-1-1-1- 4.2 1.4 1.2 .4 1.4 .37 1.3 8.3 1.3 2 1 =-= .255 3.929 1 -= .151 6.639 Wall C-3 1 1 K= --- -=-= .216 1 1 1.125 .02 1 1 4.628 -1-1-1-1-^- 4.2 1.4 1.2 .4 1.4 .43 2 Wall D-3 1 K=- 1 1 1.125 .02 1 1 1 -1- \ -1-1-1- \ - 4.2 1.4 1.2 4 .37 1.4 .43 = — = .136 7.338 2 Wall E-3 1 1 K=--=-= .229 1 .375 1 1 .75 1 4.368 -1-1-1-1-1- 4.2 1.2 .456 1.3 8.3 1.3 Wall C-2 1 1 K =--=-= . 255 1 4 1 1 .75 1 3.918 -1-1-1-1-1- 4.2 5 .99 .99 8 3 1.3 Wall F-3 1 K= -- 1 .375 1 1 1 .75 1 I-1-1-1-[-1- 4.2 1.2 .456 .37 1.3 8 3 1.3 1 -= .141 7.078 Transmission Coefficients of Roofs Roof A-1 1 1.125 1 1 .75 1 1 .75 1 5 577 -1-1-1-1-1-1-^-1- 4.2 1.2 1.4 1.4 1.2 1.4 1.3 8.3 1.3 See Page 17 Roof D-1 .179 K=--- 1 1.125 1 1 1 - 1 - 1 - 1 - 1 - 4 2 1.2 1.4 .245 1.3 1 .75 1 - 1 - 8.3 1.3 Roof B-1 1 K=- 1 1.125 1 1 .75 1 -1-1-1-1-1- 4.2 1.2 1.4 1.4 1.2 1.4 1 -=-= .104 1 1 .75 1 9.657 - 1 - 1 - 1 - 245 1.3 8.3 1.3 Roof E-1 K=- 1 .5 1 .02 .75 1 - \ - 1 - 1 - \ - 1 - 3.9 5 1.4 .4 1.2 1.4 1 1 .75 1 1 .75 1 -1-1- \ -1-1- 1.4 1.2 1 4 1.3 8 3 1.3 1 -= .132 7.602 1 - = 163 6 147 Roof C-l K=- 1 1 1.125 1 1 .75 1 -1-1-1-i-1- 4.2 12 1.4 1.3 8.3 1.3 1 -= .281 3.522 Roof F-1 1 1 X=----= - - = .098 1 5 1 .02 .75 1 1 .75 1 1 1 75 1 10.229 - 1 - 1 - \ - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 3.9 5 1.4 .4 1.2 1.4 1.4 1.2 1.4 .245 1.3 83 1 3 14 Heat Insulation for Houses Heat Transmission of Stucco Walls %" Plaster, wood lath 2"x4" Studding 6" D®.M Sheathing Building paper l"x2" Furring strips Portland stucco on metal lath Plaster, wood lath 2"x4" Studding 1/2" Flax-li-num 6 " Dca,M Sheathing Building paper l"x2'' Furring strips Portland stucco on metal lath Wall A-1 Transmission . . . . K=.242 Wall B-1 Transmission . . . . K=.146 %" Plaster, wood lath 2"x4" Studding l"x6" Byrkett sheathing Portland stucco on Byrkett sheathing %" Plaster, wood lath 2"x4" Studding 1/2" Flax-Ii-num l"x6" Byrkett sheathing Portland stucco on Byrkett sheathing Wall C-1 Transmission . . . . K=287 Wall D-1 Transmission . . . . K=.161 %" Plaster, wood lath 2"x4" Studding Portland stucco on metal lath %" Back plastering between studs Plaster, wood lath 2"x4" Studding V 2 " Flax-Ii-num Portland stucco on metal lath Back plastering between studs Wall E-1 Transmission . . . . K=.357 Wall F-1 Transmission . . . . K=181 Heat Insulation for Houses 15 Heat Transmission of Brick and Tile Walls Plaster, wood lath 2"x4'' Studding 6" D^s-M Sheathing Building paper Face Brick ^/b' Plaster, wood lath Studding V2" Flax-li-num D®.M Sheathing Building paper Face Brick Wall A-2 Transmission K=.210 Wall B-2 Transmission K=.133 Vb Plaster, on Tile 8"x5"xl2" Hollow Tile Face Brick ^/b" Plaster, on Flax*li-num Keyboard as plaster base V'xl'' Furring strips 8"x5"xl2" Hollow Tile Face Brick Wall C-2 Transmission . . . . K=.255 Wall D-2 Transmission K-.141 ^b' Plaster, wood lath T'x 2" Furring strips Common Brick Face Brick Plaster, on Flax-li*num Keyboard as plaster base l"x2'' Furring strips Common Brick Face Brick Wall E-2 Transmission K=.191 Wall F-2 Transmission K=.146 16 Heat Insulation for Houses Heat Transmission of Frame Walls %" Plaster, wood lath 1 ^ z' 2"x4" Studding 1 i 6" D®-M Sheathing 4 / Building paper W Siding k W t| % Plaster, wood lath 2"x4" Studding 1/2" Flax'li-num 6" D®.M Sheathing Building paper Siding Wall A-3 Transmission . , . . K=.255 Wall B-3 Transmission . . . . K=.151 / / V—t %" Plaster Lumber substitute as plaster base 2"x4" Studding 6" D®.M Sheathing Building paper Siding %" Plaster 7,6 Lumber substitute as plaster base 2"x4'' Studding ^ 2 " Flax'li-num 6" D<®.M Sheathing Building paper Siding Wall C-3 Transmission . . . . K=.216 Wall D-3 Transmission . . . . K=.136 Plaster, wood lath 2"x4" Studding 7,6 Lumber substitute as sheathing Siding Wall E-3 Transmission . . . . K=.229 Plaster, wood lath TjJ 2'^x4" Studding h i/ 1/2" Flax-ll-num W [/ \ V 7,6 Lumber substitute 1' as sheathing 1 Siding A i ;/ Wall F-3 Transmission . . . , Heat Insulation for Houses 17 Heat Transmission of Roofs Ceiling and Roof A Transmission. K=.179 Wood shingles l" Roof boards 2"xA" Roof rafters 2"x4'' Collar beams % Plaster on wood lath Ceiling and Roof C Transmission. K=.284 Ornamental roof tile 1" Roof boards -paper 2"x6" Roof rafters T'x6" D<®-M Flooring 2"x8" Ceiling joists Plaster on wood lath Ceiling and Roof E Transmission. K=.163 Wood shingles l" Roof boards 2"x4" Roof rafters l"x6" D®-M Flooring 2"x6" Ceiling joists 1 " Flax-li*num Furring strips on joists Plaster on wood lath Ceiling and Roof B Transmission. K=.104 Wood shingles 1" Roof boards 2"x4" Roof rafters 2''x4" Collar beams 1 " Flax*li*num Furring strips Ts" Plaster on wood lath Ceiling and Roof D Transmission. K=.132 Ornamental roof tile 1" Roof boards -paper 2"x6" Roof rafters T'x6" D'S-M Flooring 2"x8" Ceiling joists 1 " Flax-li-num %" Plaster on wood lath Ceiling and Roof F Transmission. K=.098 18 Heat Insulation for Houses Determining the Net Fuel Saving on Actual Houses EAT insulation cannot save all the heat wasted in a house. Neither “in¬ filtration” nor ventilation is eliminated by heat insulation. Losses due to conduction and radiation through windows are not affected. The ques¬ tion arises, “How much is the net saving on an actual house?” The net saving varies with every plan. To illustrate the saving and to show that it is real and tangible, three houses are here shown. Each has been considered with each of the walls shown on pages 14,15 and 16, and with insulated and uninsulated roofs shown on page 17. Total heat losses have been computed for the de¬ termination of radiation. The insulated houses show a marked reduction in radiation requirements, which are directly proportional to the total heat loss. Fuel consumption based on heat losses, as¬ suming an average temperature difference for the vicinity of St. Paul, Minnesota. The heating season is taken at 210 days with an average temperature difference of 38° Fahrenheit over this period {U. S. Weather Bureau Reports) or 7980 Degree-days. A correction must be made for the locality in which the building is to be erected. The heat transmission used for walls and roofs are those shown on the charts, pages 14,15,16 and 17, the derivation of which has been given on page 13. The houses were assumed to have double sash which has a heat transmission .45 B. t. u. Value of hot water radiation is taken as 156 B. t. u. per square foot. Maximum heat loss, to de¬ termine size of radiators and of necessary heating plant, is computed with inside temperature of 70° and outside temperature of 20° below zero. (90° Fahrenheit temperature difference.) In figuring coal saving 7,200 B. t. u. are taken as the useful heat from anthracite coal, per pound, as fired under average conditions. (Harding a Willard.) In figuring fuel oil or gas it will be necessary to calculate the consumption on the basis of the efficiency of the burner and on the available heat in these fuels. Heat losses through windows and heat losses due to infiltration are assumed to be the same where insulation is used as where no insulation is used. Heat loss due to infiltration will in actual practice vary, depending upon the wall, and window- and door-frame construction. Calking around win¬ dows, well fitted insulation, beam fills, storm sash and weather stripping all cut down air infiltration. Houses insulated with Flax-li-num placed between the studding let through less air than if no such material were in place. For this reason actual in¬ sulated houses show bigger fuel savings than those indicated here. Infiltration is a variable factor and the following data have been based on the same infiltration for the insulated and non-insulated house. Infiltration is taken as N equals 1. That is, one complete air change takes place in the house every hour. Key to Syinhols Used in the Following Comyutations H = Total heat in B. t. u.’s W = Wall surface in square feet G = Glass surface in square feet C = Ceiling surface in square feet V = Volume of air in cubic feet N = No air changes per hour (Infiltration) Ti = Room temperature To = Outside temperature Kw = Heat transmission constant for wall Kg = Heat transmission constant for glass Hw = Heat in B. t. u. transmitted through wall per hour or KwW (Ti—To) Hg = Heat in B. t. u. transmitted through glass per hour or KgG (Ti —To) Ha = Heat in B. t. u. lost by infiltration per hour or .O^VN (Ti—To) He = Heat in B. t. u. transmitted through ceiling per hour KeC (Ti—To) Heat Insulation for Houses 19 I I I FIR.ST FLOOI^ CE-IUING HEIGHT a 4-' SECOND FLOOR. CEILING HE.IGHT 6 ' O" Floor Plans and Elevation of Two Story House Copyright 1924—The Architects’ Small House Service Bureau—Home Plan No. 6A17 , Northwestern Div. Inc. 20 Heat Insulation for Houses Radiation and Fuel Savings on a House (ARCHITECTS’ SMALL HOUSE SERVICE BUREAU PLAN NUMBER 6A17 ON PAGE 19.) \V = 1872 Square Feet Wall Surface C = 176 Sq. Ft. at Roof Constant V = 11,880 Cu. Ft. Volume G=211 Square Feet Glass Surface Cl = 484 Sq. Ft. at Eave Line Constant Stucco Finished Walls (Page 14) A-l B-l C-l D-l E-l F-l Kw. .242 .146 .287 .161 .357 ! .181 Kc. .45 .45 .45 .45 .45 .45 Kc. .179 .104 .179 .104 .179 .104 Kcl. .220 .116 .220 .116 .220 .116 IIw . 40,772 24,598 48,354 27,124 60,147 30,544 lie. 8.546 8,546 8,546 8,546 8,546 8,546 lie. 2,835 1,647 2,835 1,647 2,835 1,647 IlCT. 9,583 5,053 9.583 5,053 9,583 5,053 Hv. 21.384 21,384 21,384 21,384 21,384 21,384 Total. 83,120 61,230 90,702 63,754 102,495 67,174 10% for Exposure. 8,312 6,123 9,070 6,375 10,250 6,717 Total Loss per Hour. 91,432 67,353 99,772 70,129 112,745 73,891 Total Radiation Required. 610 449 665 468 752 492 Coal in Tons per Season. 13.6 9.9 14.8 10.2 16.7 10.7 Brick Finished Walls (Page 15) A-2 B-2 C-2 D-2 E-2 F-2 Kw. .210 .153 .255 .141 .191 .146 Kg. .45 .45 .45 .45 .45 .45 Kc. .179 .104 .179 .104 .179 .104 Kcl. .220 .116 .220 .116 .220 .116 Hw. 35,381 22,408 42,962 23,756 32,179 24,598 Hg. 8,546 8,546 8,546 8,546 8,546 8,546 lie. 2,835 1,647 2,835 1,647 2,835 1,647 Hcl. 9,583 5,053 9,583 5,053 9,583 5,053 Hv. 21,384 21,384 21,384 21,384 21,384 21,384 Total. 77.729 59,038 85,310 60,386 74,527 61,228 10% for Exposure. 7,773 5,904 8,531 6,039 7,453 6,123 Total Loss per Hour. 85,502 64,942 93,841 66,425 81,980 67,351 Total Radiation Required. 570 433 626 443 547 449 Coal in Tons per Season. 12.6 9.6 13.8 9.8 12 1 9.9 Siding Finished Walls (Page 16) A-3 B-3 C-3 D-3 E-3 F-3 Kw. .255 .151 .216 .136 .229 .141 Kg. .45 .45 .45 .45 .45 .45 Kc. .179 .104 .179 .104 .179 .104 Kcl. .220 .116 .220 .116 .116 .116 Hw. 42,962 25,440 36,391 23,072 38,582 23,756 Hg . 8,546 8,546 8,546 8,546 8,546 8,546 He. 2,835 1,647 2,835 1,647 2,835 1,647 Hcl . 9,583 5,053 9,583 5,053 9,583 5,053 Hv. 21,384 21,384 21,384 21,384 21,384 21,384 Total. 85,310 62,070 78,739 59,702 80,930 60,386 10% for Exposure. 8,531 6,207 7,874 5,970 8,093 6,039 Total Loss per Hour. 93,841 68,277 86,613 65,672 89,023 66,425 Total Radiation Retjuired. 629 456 577 438 594 443 Coal in Tons per Season. 13.8 10.0 12.9 9.6 13.2 9.8 Heat Insulation for Houses 21 Comparison of Required Radiation and Fuel Consumption m H ouses Built from the Same Plan with Common Types of Walls and Roofs (ARCHITECTS’ SMALL HOUSE SERVICE BUREAU PLAN NUMBER 6A17, Page 19.) NON-INSULATED HOUSE INSULATED HOUSE (Identical, except for Insulation) Wall Number Value of K Radiation Required Tons of Coal per Season Wall Number Value of K Radiation Required Tons of Coal per Season A-1 .242 610 13.6 B-1 .146 449 9.9 C-1 .287 665 14.8 D-1 .161 468 10.2 E-1 .357 752 16.7 F-1 .181 492 10.7 A-2 .210 570 12.6 B-2 .133 433 9.6 C-2 .255 626 13.8 D-2 .141 443 9.8 E-2 .191 547 12.1 F-2 .146 449 9.9 A-3 .255 629 13.8 B-3 .151 455 10.0 C-3 .216 577 12.9 D-3 .136 438 9.6 E-3 .229 594 13.2 F-3 .141 443 9.8 Average. .249 619 13.7 .148 452 9.9 Saving thru Ceiling of Above House .179—.104 =41.9 Per Cent .179 Saving thru Average Walls .249—.148 =40.6 Per Cent .249 Average Saving on Radiation 619—452 =27.0 Per Cent 619 Average Saving in Fuel per Season 13.7—9.9 =27.8 Per Cent 13.7 When it is 90 degrees outside, the in¬ terior of the /^/ax-Zi-ntim-insulated home is 10 to 15 degrees cooler. When it is 20 below outside, the tem¬ perature of a Flax-li-num-Ymed home is easily maintained at 70 degrees. 22 Heat Insulation for Houses Heat Losses on Bungalow Type Houses HE more compactly a house is designed the lower will be the fuel bill per cubic foot of space. Square and rectangular houses burn less fuel than those of more complex design. Fuel bills alone do not govern the design of houses. It is advisable however to take cognizance of house types that increase heat losses and where these types are employed to reduce the losses by the proper application of the correct building insulation. One of the most common of the high-heat-loss types is the one-story bungalow and its modifica¬ tion, the story and a half house. In this class may be included all houses with relatively large roof areas and without attic floors or finished rooms above the first floor. This includes a great many houses of the Dutch Colonial type and most houses of the smaller English Cottage type. One cause for the higher heat loss in this house- type lies in the construction of the roof and ceiling. Where the roof and ceiling combination of the two-story house (pages 20 and 21), including the attic floor, without heat insulation is .179 B. t. u., the roof of the one-story and Dutch Colonial types (pages 24 and 25) is .284 B. t. u. (See Roofs A and C. Page 17.) The relation between these two roof types is as follows: with 1 X 2’s to receive lath and j^laster cuts the transmission from .284 to .132 B. t. u. This es¬ tablishes the relation between the insulated and uninsulated roof as follows: Saving in heat transmission thru ceiling and roof combination. (One-Story Bungalow) This saving of 50.3 percent is to be compared with the following saving made by insulating the roof of the full two-story house: Saving in heaC transmission thru ceiling and roof com¬ bination. (Two-Story House) .284 —.132 - =-■ 50.3% .284 .179 —.104 -- 12 % .179 Difference in heat transmission thru roof of bungalow and two-story house. .284 —.179 - = 37% .284 This percentage is somewhat reduced by the cor¬ rection made on the two-story type for convection around the attic floor at the eave line. In a great manv houses much of the benefit of the attic floor t. is lost by poor construction at that point. If tlie heat loss through bungalow roofs is higli, great reductions can l)e made by properly heat in¬ sulating these roofs. One inch Flax-li-num applied to the under side of the ceiling joists and furred out It will be seen from the above that the unit loss per square foot of roof area is greater in the one- story house. And since there is usually a larger proportional roof area on this type of house the total heat losses are noticeably larger. The need for heat insulation is therefore greater and the sav¬ ings made by heat insulation, are larger than on the two-story types. To illustrate the savings made by heat insulating houses of this type a simple one-story bungalow is figured in the same way as the two-story house. Like the two-story type this home is shown with all applicable wall constructions. Heat Insulation for Houses 23 24 Heat Insulation for Houses Radiation and Fuel Savings on a House (ONE STORY BUNGALOW ON PAGE 23.) W = 1005 Square Feet Wall Surface C = 1060 Square Feet of Ceiling Surface G = 162 Square Feet Glass Surface V = 9010 Cubic Feet Volume Stucco Finished Wall Number (Page 14) A-l B-1 C-l D-l , E-l F-l Kw. .242 .146 .287 .161 .357 .181 K(;. .45 .45 .45 .45 .45 .45 Kc. .284 .132 .284 .132 .284 .132 Hw. 21,889 13,206 25,959 14,562 32.291 16,375 Hg. 6,561 6,561 6.561 6,561 6,561 6,561 He. 27,093 12,593 27,093 12.593 27,093 12,593 Hv. 16,218 16,218 16,218 16,218 16,218 16,218 Total. 71,761 48,578 75,831 49,934 82,163 51,747 10% for Exposure. 7.176 4,858 7.583 4,993 8,216 5,175 Total Loss per Hour. 78,937 53,436 83,414 54,927 90,379 56,922 Total Uadiation Required. 526 356 556 367 603 379 Coal in Tons per Season. 11.7 7.9 12.3 8.1 13.3 8.4 Brick Finished Wall Number (Page 15) A-2 B-2 C-2 D-2 E-2 F-2 Kw. .210 .133 .255 .141 .191 .146 Kg . .45 .45 .45 .45 .45 .45 Kc. .284 .132 .284 .132 .284 .132 Hw. 19,805 11,830 23,065 12,753 17,276 13,206 Hg. 6,561 6,561 6,561 6,561 6,561 6,561 He. 27,093 12,593 27,093 12,593 27,093 12,593 Hv. 16,218 16,218 16,218 16,218 16,218 16,218 Total. 69,677 47,202 72,937 48,125 67,148 48,578 10% for Exposure. 6,968 4,720 7.294 4,812 6,715 4,859 Total Loss per Hour. 76,645 51,922 80,231 52,937 73,863 53,437 Total Radiation Required. 512 346 535 353 493 356 Coal in Tons jier Season. 11.3 7.0 11.8 7.8 11.0 7.9 Siding Finished Wall Number (Page 16) A-3 B-3 C-3 D-3 E-3 F-3 Kw. .255 .151 .216 .136 .229 .141 Kg. .45 .45 .45 .45 .45 .45 Ke. .284 .132 .284 .132 .284 .132 Hw. 23,065 13,658 19,537 12,282 20,713 12,753 Hg 6,561 6,561 6,561 6,561 6,561 6,561 He. 27,093 12,593 27,093 12,593 27,093 12,593 Hv. 16,218 16,218 16,218 16,218 16,218 16,218 Total. 72,937 49,029 69,409 47,654 70.584 48,125 10^ for Ex])osure. 7,294 4,903 6,941 4,765 7,059 4,812 Total Loss ])er Hour. 80,231 53,932 76,359 52,419 77,643 52,937 Total Radiation Retjuired. 535 360 509 349 518 353 Coal in Tons jier Season. 11.9 8.0 11.3 7.7 11.5 7.8 Heat Insulation for Houses 25 Comparison of Required Radiation and Fuel Consumption in Houses Built from the Same Plan with Common Types of Walls and Roofs (ONE STORY BUNGALOW, PAGE 23) NON-INSULATED HOUSE INSULATED HOUSE Wall Number Value of K Radiation Required Tons of Coal per Season Wall Number Value of K Radiation Required Tons of Coal per Season A-1 .242 526 11.7 B-1 .146 356 7.9 C-1 .287 556 12.3 D-1 .161 367 8.1 E-1 .357 603 13.3 F-1 .181 379 8.4 A-2 .210 512 11.3 B-2 .133 346 7.0 C-2 .255 535 11.8 D-2 .141 353 7.8 E-2 .191 493 11.0 F-2 .146 356 7.9 A-3 .255 535 11.9 B-3 .151 360 8.0 C-3 .216 509 11.3 D-3 .136 349 7.7 E-3 .226 518 11.5 F-3 .141 353 7.8 Average. .248 532 11.8 .... .148 358 7.8 Saving thru Ceiling of Above House .284—.132 = 53.5 Per Cent .284 Saving thru Average Insulated Walls .248—.148 =40 Per Cent .248 Saving in Radiation, average 532—358 =32.7 Per Cent 532 Average, Saving in Fuel per Season 11.8—7.8 =33.9 Per Cent 11.8 The pioneer New Englanders filled the hollow walls of their log cabins with grass and straw bound together with mud.—Primitive Insulation. The occupants of a Flax-li-num- lined house are completely enclosed by a heat-resisting material that keeps the heat in during the winter and out during the summer. 26 Heat Insulation for Houses ' T I 1 51 ■' L CC H P I 4 M ' ' i. . *• -c.' 5lC ON D [LOOL flAN' s c » L t i, • I-o‘ Floor Plans and Elevation of a Larger House Heat Insulation for Houses 27 Comparison of Required Radiation and Fuel Consumption in a Larger House SEE FRONTISPIECE (PAGE 2) AND PAGE 26 W =3135 Square Feet Wall Surface C = 2637 Square Feet of Ceiling Surface G =598 Square Feet Glass Surface V = 36080 Cubic Feet Volume Wall Number Ceiling Number A-2 C-1 B-2 D-1 Kw. .210 .133 Kc. .284 .132 Kg. .45 .45 Hw. 59,252 36,526 He. 67,302 31,328 Hg. 24,219 24,219 Hv. 64,944 64,944 Total. 215,717 158,017 10% for Exposure. 21,572 15,802 Maximum Loss per Hour. 237,289 173,819 Total Rad. Req., Hot Water. 1,582 1,159 Total Rad. Req., Vapor. 989 724 Coal in Tons per Season. 35.0 25.6 Saving thru Ceiling of Above House .284—.132 =53.6 Per Cent .284 Saving thru Wall .210—.133 =36.8 Per Cent ^210 Saving in Radiation 1582—1159 =26.7 Per Cent 1582 Saving in Fuel per Season 35.0—25.6 =26.7 Per Cent 35.0 Note—T o simplify computations all walls have been taken as brick veneer, although small parts of the top story are actually stucco and half timber. It requires less fuel to properly heat a Flax-li-num-lined house. Fuel bills average 30% less where Flax-U-num is used. Flax-li-num has been tested and proved in thousands of buildings in every section of the country for more than seventeen years. 28 Heat Insulation for Houses Suggestions for Specifying Heat Insulation \'ERY Flax-li-num specification is designed to take advantage of scientific principles—to give the greatest return at the most reasonable cost. The experience of a seasoned organization of highly trained engineers, plus sev¬ enteen years of actual use in thousands of homes and industrial jobs, form the sound basis for Flax-li-num specifications. There are four things to cover in specifying Heat Insulation. The wording may vary, but unless the following points are plainly covered, the client is not likely to secure the full benefit from his insulation. 1. Placing or Application Specify the exact places where insulation is to go. The effectiveness of heat insulation is increased if applied between studdings, midway between the sheathing and lath and plaster on frame con¬ struction, or furred out on masonry construction. Effectiveness is increased when heat insnlation goes bet 01 V top story ceiling joists instead of over them or on the rafters. Effectiveness is decreased by applying insulation out¬ side of sheathing, or by using as a plaster base. Elax-li-num should be ap- l)lied as shown here; the ]/ 2 ' hanged material as de¬ scribed above; the one-inch material below top story ceiling joists, with the sheets paralleling the joists. Elax-li -nuni for ceiling insulation is made 32" wide so as to make all edges come directh^ below ceiling joists set 16 inches on centers. The hanged material is and 24)^" wide, made to ht between studs spaced 16 or 24 inches on centers. Applying Half-Inch Flanged Flax-li-num in frame walls Quick, easy and efficient 2. Thickness of Material Laboratories, in their reports, give the transmis¬ sion of insulating materials on the basis of one inch of thickness. Most materials as actually sold are only a fraction of that thick¬ ness, thus necessitating the computation of transmis¬ sion coefficient for the thickness furnished. The benehts of true heat insula¬ tion come where at least one-half inch of Elax-li-num is used in walls in addition to all other standard parts of the wall, such as sheathing, lath, building paper, etc. In roofs, where the greatest heat losses occur, true heat insulation means Elax-li-num one inch thick. 2. Raw Material and Form xMter trials and tests upon many raw materials and every form of insulation, the makers of Elax-li- num settled upon purified flax and semi-rigid board form, as the most efficient and practical. Elax-li-num is pure flax. There is no other material used in its manufacture. It is felted together; there is no “binder” or foreign substance that might vary in strength or lose its efficiency in the course of years. Elax fibre is the basis for linen, the oldest and Most efficient way to apply Roof In¬ sulation. One-Inch Flax-li-num on under side of top story ceiling joists Heat Insulation for Houses 29 most durahle of fa])rics. In the form of “Tow” it fills most of our ii])holstered furniture. These uses indicate the durability and long life of the raw material. Flax-li-iium has been taken out of Rail¬ road Refrigerator Cars after fifteen years of service in such good condition that it was used again in the rebuilt cars. This has occurred not in single This is One-Inch Flax-li-nitm. Insvlation for House Roofs should be this thick. instances, but in whole series of cars numbering into the thousands. The semi-rigid form was chosen as giving the highest insulating efficiency combined with dura¬ bility, ease of application and long life, thus making it a practical building material. Flax-li-num is flexible enough to fit around un¬ even places and to make tight joints with studdings, joists or rafters. It takes up shrinkage of timbers and settlement of buildings without tearing or pulling away. It cannot warp or buckle. Yet it is not flimsy. Workmen can handle it without the extreme care that slows up construction. It does not tear or puncture. The petty accidents of construction leave its efficiency unimpaired. And it is guaranteed to stay in place, at fidl effi¬ ciency, as long as the building stands. Workmanship Correct and workmanlike application is as es¬ sential in insulation as in any other detail of con¬ struction. It is necessary that the contractor be furnished with a definite specification which will take care of important details, and that this spec¬ ification be followed in an intelligent manner, with a view to the results which are expected. All window and door frames should be thoroughly calked with scrap pieces of Flax-li-num. A con¬ scientious builder, by careful work around the windows, by notching and flanging Flax-li-mim sheets at the top and bottom and by seeing that sheets of such length are used that the insulation may be a continuous sheet from plate to plate, can increase greatly the comfort of the insnlated home. We recommend as a heat saver the double window casing, and further recommend the beam fill as a barrier to the entrance of heat and cold at the foundation line. The principal reason for headers at the ceiling line in gables is to provide a heat stop and a nailing base for the top of Flax-li-num sheets at that point. LIST OF FLAX-LI-NUM SPECIFICATIONS 4- A. Insulation for a storv-and-a-half semi-bungalow --------- Page 31 13- A. Insulation for a one or two storv house ------------- Page 33 8-x4. Insulation for brick veneer houses or two flats - -- -- -- -- - Page 35 ll-A. Flax-li-num Keyboard—heat insu¬ lation and plaster base for brick and hollow tile houses, bungalows or two flats - -- -- -- -- - Page 37 3-A. Sound Control—side wall and roof insulation, where studding is brok¬ en at ceiling line ------- Page 43 7-A. Sound Control—side wall and roof insulation, where studding is not broken at ceiling line ----- Page 45 5- A. Sound Control and roof insulation where outside walls are of brick or hollow tile - -- -- -- -- - Page 47 2-A. Heat insulation for flat roof decks of concrete or wood ------ Page 55 14- x4. Heat insulation for steel deck roofs Page 57 30 Heat Insulation for Houses ^ ft JS/r ••^. e»0!//fog .s «'■-.' s /.f, .^FTTfow /'Mm A%7;. :■ • 'i' .::fo.:m^^ fe* A/i ''^,:f: 'fo^^^yi^//'t Header Important Calk Window Frames and Door Jambs Thoroughly with Scrap Pieces of Flax-li-num ^0m Siding~^ Paper Sheathing Yl' Flanged for Wall Insulation Air Space Lath Plaster Studding Flax-li-num r F Heat Insulation for Houses 31 Insulation for a Story and One-Half Semi-Bungalow Standard Specification No. 4-A [As Per Detail on Opposite Page] SIDE WALL INSULATION (1) Materials: Heat Insulation for all outside walls shall be 3^" Flanged Flax-li-num, manufaetured by the Flax-li-nnm Insulat¬ ing Company, St. Paul, Minn. (2) Application: Flanged Flax-li-num sheets shall be applied be¬ tween studdings from lower to top plate. Top and bottom of sheets shall be notched and flanged into place. Binding strips (lath) shall be securely nailed through flanged edges and top and bottom of Flax-li-num sheets to studdings and plates (to insure tight joints). In gables, blocks of studding dimension shall be inserted between studding flush with bottom edge of ceiling joists. Insulation shall be run to these headers and fastened to them with lath. (Detail on opposite page.) ROOF INSULATION (3) Materials: Heat Insulation for the roof shall be 1'' Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. (4) Application: 1" Flax-li-num Flat Sheets shall be applied to the under side of rafters and collar beams. At intersection of rafters and collar beams wood headers shall be placed between rafters and insulation fastened to these headers (to provide tight joints). Insulation shall be furred out with 1 x 2’s over rafters and collar beams to receive lath and plaster. At all end joints of insulation insert wood headers and nail both sheets to these headers to insure tight joints. 32 Heat Insulation for Houses 1" on Ceiling for Roof Insulation Header Important Siding Sheathing Flax-li-num Lath 86 Plaster Calk Window Frames and Door Jambs Thoroughly with Scrap Pieces of Flax-li-num 34 Flanged for Wall Insulation t %. t -Vi k ^ ~ > V. e » V'f;? ■»# Heat Insulation for Houses 33 Insulation for a One- or Two-Story House Standard Specification No. 13-A [As Per Detail on Opposite Page] SIDE WALL INSULATION (1) Materials: Heat Insulation for all outside walls shall be 3^" Flanged Flax-li-num, manufactured by the Flax-li-num Insulat¬ ing Company, St. Paul, Minn. (2) Application: Flanged Flax-li-num sheets shall be applied be¬ tween studding from lower to top plate. Top and bottom of sheets shall be notched and flanged into place. Binding strips (lath) shall be securely nailed through flanged edges and top and bottom of Flax-li-num sheets to studdings and plates (to insure tight joints). In gables, blocks of studding dimension shall be inserted between studding flush with bottom edge of ceiling joists. Insulation shall be run to these headers and fastened to them with lath. (See detail opposite.) ROOF INSULATION (3) Materials: Heat Insulation for the roof shall be 1" Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. (4) Applicatiori: 1" Flax-li-num flat sheets shall be applied to the under side of top floor ceiling joists. Insulation shall be furred out with 1 X 2’s under joists to receive lath and plaster. At all end joints of Flax-li-num insert wood headers and nail both sheets to these headers to insure tight joints. 34 Heat Insulation for Houses Heat Insulation for Houses 35 Heat Insulation for Brick Veneer Houses Standard Specification No. 8-A [As Per Detail on Opposite Page] HEAT INSULATION FOR WALLS (1) Materials: Heat Insulation for outside walls shall be 3^" Flanged Flax-li-num, manufactured by the Flax-li-nuin Insulating Com¬ pany, St. Paul, Minn. (2) Application: Y 2 ' Flanged Flax-li-num sheets shall be applied between studding from lower to top plate. Top and bottom of sheets shall be notched and flanged into place. Binding strips (lath) shall be securely nailed through flanged edges and top and bottom of Flax-li-num sheets to studdings and plates (to insure tight joints). In gables, blocks of stud dimension shall be in¬ serted between studding flush with bottom edge of ceiling joists. Insulation shall be run to these headers and fastened to them with lath. On outside of sheathing apply building paper and lay up brick in regular manner. ROOF INSULATION (3) Materials: Heat insulation for the ceiling of the top story shall be 1" Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. (4) Application: 1" Flax-li-num flat sheets shall be applied to the under side of top floor ceiling joists. Insulation shall be furred out with lx2’s under joists to receive lath and plaster. At all end joints of Flax-li-num insert wood headers and nail both sheets to these headers to insure air tight joints. 36 Heat Insulation for Houses Heat Insulation for Houses Heat Insulation for Brick and Hollow Tile Houses or Bungalows Standard Specification No. 11-A [As Per Detail on Opposite Page] HEAT INSULATION FOR WALLS (1) Materials: Heat insulation for all outside walls shall be Flax-li-num Keyboard manufactured by the Flax-li-num Insulating Company, St. Paul, IVIinn. (*2) Millwork: Window and door frames shall be made to aceommodate thickness of wall plus furring strips plus 3^" extra thickness for Keyboard. (3) Application: In laying tile walls insert lath horizontally into mortar joints every two feet. To these lath nail 1x2 furring stri])s vertically, on 16" centers. x4pply Flax-li-num Keyboard, breaking vertical joints every 3 feet. Nail each lath on Keyboard into every furring strip with 6d nail. Apply plaster in usual manner, covering lath to a depth of ^ inch. between first and second floors insert small pieces of Keyboard or flanged Flax-li-num between joists to properly insulate this space. ROOF INSULATION (4) Materials: Heat insulation for the roof shall be 1" Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. (5) Application: 1" Flax-li-num flat sheets shall be applied to the under side of top story ceiling joists. Insulation shall be furred out with 1 x 2" under joists to receive lath and plaster. At all end joints of Flax-li-num insert wood headers and nail both sheets to these headers to secure tight joints. Flax-li-num Keyboard—A Plaster and Stuceo Base that Really Insulates The use of Flax-li-num Keyboard offers many advantages to the man who plans to build a stucco house, or one of masonry construction, that are not found in the ordinary plaster and stucco base and the ordinary insulating material. Flax-li-num Keyboard is a combination of a correct insulating material and a time-tried and proved meehanieal-key base for plaster or stucco. Flax-li-num Keyboard is made up of one-half inch Flax-li-num, a thick sheet of waterproof, asphalt saturated paper and No. 1 pine beveled or dove-tailed wood lath. The use of best cpiality lath insures a positive mechanical key between ])laster or stucco and Flax-li-num Keyboard, and forms a base which holds the plaster or stucco permanently without danger of unsightly cracking or falling off. 38 Heat Insulation for Houses Flax-li-num Sound Control HE I’apid increase in late years of the number of apartments, the coming of the one and two room “kitchenette” apartment and the great increase in the number of families housed per apartment building which resulted there¬ from, has forced the science of sound control to the attention of archi¬ tects and engineers everywhere. Good sound control, the cutting off of sound trans¬ mission between different portions of the same structure, has always been a desirable ((iiality. It has been sought after more or less by designers of hotels, hospitals and apartments. But the problems in years past were never so acute as those encountered by the architect of today. The apartments of yesterday usually had high ceilings and there were seldom more than two to a floor. There were fewer families per building and thus fewer people using party hallways, less concentration into one or two rooms, more space per family. All these things made less necessary the scientific control of sound which is so essential in apartments today. The Moderri Apartment The modern apartment presents a different prob¬ lem. When 2.5 to 200 families occupy jointly a single l)uilding, it becomes highly essential, if privacy is to be maintained to any extent, that party walls, floors and ceilings be rendered as sound l)roof as is humanly possible. This is especially desiral)le in view of the class of tenants usually sought after for the elaborate modern apartment l)uildings. It cannot be expected that the homes of people of refinement should be subjected to the constant annoyance of their neighbor’s Radio, to the sound of walking about in the halls and of con¬ versations in the adjoining apartments, nor that their own conversations should be overheard bv their neighbors to the right or left of them. If the modern apartment is to permanently fill the j)lace it seems to have taken in the life of American cities, it must l^e made to correspond, as nearly as possible to the private home. In other words, })rivacy must be built into the structure, and it is jus t as essential that this ])rivacy be maintained as it is that the heating plant be adequate and that the service be up to standard. Without privacy, the modern apartment can never be more than a tem¬ porary dwelling place, to be endured only until bet¬ ter quarters are available. Privacy is more neces¬ sary than expensive finish, more vital than fixtures, built-in features or service. Owners are beginning to realize these facts, and they will be brought home more and more force¬ fully within the next few years. The real test of the apartment will come when home-building is resumed on an extensive scale, when competition shall exist between the apartment and the private home. If the investments that apartment owners are making today are to be permanently lucrative, the apartment will have to offer more than mere living quarters. Arrangement cannot compensate for loss of privacy. Convenience is but a matter of design. These obvious advantages must be combined with privacy secured through proper sound control. Principles of Sound Sound, like heat, is not a substance, but a vi¬ bration. Sound varies with the velocity and wave length of the vibration, differing vibrations pro¬ ducing different tones, and various materials in reflecting and magnifying sound also produce vari¬ ances of tone quality. The vibrations of a column of air differ from those of a reed, or a string. These principles govern the fashioning of all musical instruments. Sounds which combine a great num¬ ber of tone qualities, which are by far the most common, are simply known as noise, and it is this Heat Insulation for Houses 39 class of sound which makes necessary the proper treatment of party walls and floors in apartments, schools, hotels and hospitals. Sound vibrations are governed b}" the substance in which they are set u}) and the substances through which they travel. Thus, some substances are better conductors of sound than others. More¬ over, the ease with which sound may be trans¬ mitted from one point to another is proportional to the amount of resistance to the vibrations mak¬ ing up that sound. Thus, if a sound generated on a wood floor can travel along the joists, through the plate and into the studdings below, without ever leaving the wood, there has been practically no re¬ sistance to its passage. The same principle, ap¬ plied to a column of air, makes possible the speak¬ ing tube. The length of the space to be traveled is relatively unimportant. The Suspended Ceiling The above explanation makes clear, the futility of the common type of suspended ceiling as a bar¬ rier to sound transmission. Direct contact be¬ tween floor and ceiling has been cut off, but sounds set up in the wood of the floor above can travel without hindrance, through the joists, above plates and along the joists laid below. There is a con¬ tinuous wooden transmitter for the sound. CoiTect Sound Control To correctly control sound between floors, it is necessarv to cut one floor off from the other with t/ some non-conductor of sound. To place a laj^er of sound absorbing material between rough and fin¬ ished floor helps some, of course, but there is still a continuous transmission through the studdings, plates and joists. This transmission must be broken up, or a satisfactory job cannot be secured. How Sound Is Dissipated Sound carried to a material is broken up and dissipated in three ways: reflected; transmitted; absorbed. Therefore, it is possible that while a material mav l)e extrenielv low in transmission, it may be very high in reflection, eliminating it as an efficient sound controller. The test is in the ab- sorbing (piality, coupled, of course, with those qualities which are inherent in every good building material—strength, durability and ease of a])])li- cation. Specifying Sound Control In specifying sound insulation, there are four factors upon which the success or failure of the specification depends. 1st: the sound absorbing qualities of the insulation; 2nd: the strength, durability and ease of application of the material; 3rd: the manner in which the insulation is ap¬ plied; 4th: the absence of any other conductor of sound. In explanation of this fourth point, if, after the controlling system has been carefully worked out, a ventilating flue or some other duct were to be run through the building so as to touch all apartments, the effect of the insulation would be nullified. A mistake on any one of these points is very likely to seriously impair the value of the system. How Flax-li-num Fits Into the Specification Professor F. R. Watson in his text book “The Acoustics of Buildings” publishes the results of tests run to determine the sound absorption co¬ efficients of insulating materials. The co-efficient established for Flax-li-num is .55. This means that 55% of the incident sound is absorbed. Flax-li-num has the qualities that endorse it as a good building material. There is built into it enough raw material to give it, in its semi-rigid felted form, the strength, durability and ease of handling that make it a product liked by contrac¬ tors and workmen on the job. No special care need be exercised in its handling and it is readily fitted to the irregularities in construction with the least labor and trouble. 40 Heat Insulation for Houses Player Piano and Harj) Rooms of Lyon & Plealy Music Studios, Chicago, Sound Controlled with Flax-li-num. The tlfird and perhaps the most important con¬ sideration is the application. In examining the specifications that follow, it will be noted that the jmri)ose in each is to cut off absolutely, one floor from the other and one side of each partition from the other with a thickness of Flax-li-num. In the brick buildings this is done by off-setting the wall at the ceiling lines, and then applying, before set- tingpartitions, a continuous 3^'''layerof Flax-li-num to the under side of the ceiling joists. This is further protected with joist pads set over all joists below the hnished floor, and with a 3^''thickness of Flax-li-num, covering the rough floor like a carpet, the hnished hoor to be laid directly over this 14." Flax-li-num without furring strips. In the stucco, brick veneer or frame buildings where the studs are broken at the ceiling line, plate pads are inserted between stud and plate to cut off the hoors, and these form a continuous laver with the 3^'' hat sheets on the under side of the ceiling joists as in the solid brick building. The most difficult type of building to deaden is that in which the studdings run clear through. Here, it is mani¬ festly impossible to cut oh the hoors absolutely one from the other, and the only practical remedy is to insert headers of Flax-li-num between the studdings at the ceiling line, thus closing the air duct between studdings, but not, of course, stopping the direct transmission through the studding itself. Flax-li-num hnds uses in many jobs requiring special treatment for sound control. Flax-li-num was successfully used for specially constructed booths for the Lyon & Healy Com¬ pany, prominent Chicago Music house, in 1915. The following statement from this firm indicates how well Flax-li-num has performed in this un¬ usual application, leading to their use of this same material again in 1926: “For the past eleven years FLAX-LI-NUM has served as a sound eontroller in the partitions be¬ tween our talking maehine rooms so suceessfully that we are installing it in the partitions of our new player piano and harp rooms that are now being built. “Our business requires sales rooms that do not transmit any sound to the adjoining rooms. FLAX- LI-NUM fills this requirement so well that we shall continue to use it whenever the occasion demands.” Acoustical CotTcction The majority of projects in which problems of aeoustics arise require the services of expert acous¬ tical engineers in their solution. The Flax-li-num Insulating Company does not deal in generalities on this subject, therefore, and offers Flax-li-num on its record of proven merit, together with the services of trained engineers who will be glad to co-operate with architeets and engineers on the particular projects upon which they are working. Engineering Service The services of Flax-li-num engineers are avail¬ able to arehiteets and engineers, and correspond- enee is invited that we may put you in touch with the Flax-li-num serviee man nearest you. Heat Insulation for Houses 41 Details—Sound Control Applications [See Specifications 3-A, 5-A, 7-A, on Following Pages] Party Wall Framing detail, see Plate 11 Party Wall and Floor FIREPROOF construction' Party Wall and Floor FRAME construction 1 / 2 " Flax-Ii-num l"x2'' Furring strips Plaster, wood lath Plate IV V4 " Flax-Ii-num c Joist Pads ) > 1 / 2 " ^ Floor Joist r^ 1 li-num l)y| ( l"x2" Furring strips Plaster, wood lath Floor Steel Joist Wire Tie Wood StripNy 1" Flax-li-nutn Plate V Furring Strip. Metal lath and plaster STEEL Metal lath and plaster Plate VI Party Wall STEEL CONSTRUCTION 42 Heat Insulation for Houses Screened Louvre 1" on Ceiling for Roof Insulation Sheathing lax-li-num Paper Air Space Brick Heat Insulation for Houses 43 Sound Control, Side Wall and Roof Insulation where Studding IS Broken at Ceiling (Platform Construction) Standard Specification No. 3-A [As Per Detail on Opposite Page, Also Page 41] SOUND CONTROL (1) Materials: Shall be 3^" Flax-li-niim flat sheets, 3^" Flax-li-num Joist and Plate Pads, and 3^" Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. (2) Application: Before placing joists all top plates shall be covered with 3^" Flax-li-num Plate Pads (the width of the plates). Flax-li-num Joist Pads 3/2 ^^x3"x 3' are to be placed on top edge of all joists and headers to receive floor¬ ing, which is to be laid diagonally and tight. All lower plates are to be placed on }/ 2 ' Flax-li-num Plate Pads, which will project on each side of the plates on partition walls, and on the inside of outside walls, to receive grounds for lath and plaster. Before lathing, ceiling of lower floors shall be covered with ]/ 2 ' Flax-li-num flat sheets applied to the bottom edge of the ceiling joists, all joints to be well fitted and butted tight (to receive end joints, 1x2 headers shall be placed between the joists). Headers, joist dimensions, shall be placed between the joists over all bearing sound controlled partitions. Extra joist shall be placed directly over and below where sound controlled partitions parallel the joists. Under floors are to be covered with a continuous thickness of 3^" Flax-li-num fitted tight against the plate pads and finished floor is to be laid directly over Flax-li-mim (no furring strips). (3) Party Partition Sound Control Application, see paragraph No. 3, Specification 7-A, page 45, and Details 1, 2 and 4, page 41. ROOF INSULATION (J) Material: Shall be V Flax-li-num flat sheets, manufactured by the Flax-li- num Insulating Co., St. Paul, Minn. (5) Application: Before placing partitions, 1" Flax-li-num flat sheets shall be applied to the under side of the top floor ceiling joists, to be butted tight against plate and ribbon board and furred out over joists with lx2’s for lath and plaster. At top floor ceiling line, headers, stud dimension, shall be placed between studs. SIDE WALL INSULATION (6) Material: Shall be 3^" Flax-li-num flanged or flat sheets, manufactured by the Flax-li-num Insulating Co., St. Paul, Minn. (7) Application (1): Flanged Flax-li-num shall be applied in accordance with paragraph No. 2, Specification 13-A, page 33. (8) Application (2): From foundation to top floor ceiling line 34" Flax-li-num flat sheets shall be applied to the outer side of the sheathing. Flax-li-num shall be covered with a good grade of asphalt saturated paper and furred out over studding with lath. End and side joints are to be butted tight. x4bove top floor ceiling line fur outside of sheathing with lx2’s and lay up walls. 44 Heat Insulation for Houses Screened Louvre 1" on Ceiling for Roof Insulation /"A- END JOINT Flax-li-num Headers Very Important Mt ':.F ^ ^ ? -a. Heat Insulation for Houses 45 Sound Control, Side Wall and Roof Insulation where Studding is not Broken at Ceiling Line (Balloon Construction) Standard Specification No. 7-A [As Per Detail on Opposite Page, Also Page 41] SOUND CONTROL (1) Materials: Shall be Flax-li-num flat sheets, ]/ 2 ' Flax-li-num Joists and Plate Pads, 3^" Flax-li-num headers and Flax-li-num flat sheets, manu¬ factured by the Flax-li-num Insulating Co., St. Paul, Minn. {2) Floor Sound Control plication: Flax-li-num Joist Pads 3/2^^x8"x3' to be placed on top edge of all joists to receive under flooring which is to be laid diagonally and tight. At ceiling line and at floor line above, on all floors, 3^" flanged Flax-li-num headers are to be fitted tightly between studdings in such a manner as to completely close openings. Before lathing, ceiling of lower floors shall be covered with a continuous layer of 3^" Flax-li-num flat sheets nailed to under side of joists. All joints shall be fitted and butted tight against Flax-li-num headers which are between studdings. Under joists Flax-li-num shall be furred out with 1x2's for lath and plaster. (3) Party Wall Control Application: (See Details 1, 2 and 4, page 41.) Lay 3/^"x4" Flax-li-num pads on sleepers below partitions before placing floor joists. Cut off corners of joists so that joists from one side of partition will not touch floor on the other side. Place 3^"x6" Flax-li-num pads between joists that support floor on one side of partition and joists that support floor on the other side. Insert wood headers, joist dimension, between joists directly under partition, separating headers from the joist with 3^"x3" Flax- li-num pad. Lay 3^"x4" Flax-li-num pads over these headers and inter¬ sections of joists and lay plate directly on pads. Apply 3^" Flax-li-num sheets to partition on both sides running Flax-li-num down to and butting against Flax-li-num pads under plate. ROOF INSULATION (4) Material: Shall be 1" Flax-li-num flat sheets, manufactured by the Flax-li- num Insulating Co., St. Paul, Minn. (5) Application: Before placing partitions 1" Flax-li-num flat sheets shall be applied to the under side of the top floor ceiling joists, to be butted tight against joist and ribbon board and furred out over joists with lx2’s for lath and plaster. At top floor ceiling line, headers, stud dimension, shall be ])laced between studs. SIDE WALL INSULATION (6) Material: Shall be 3^" Flax-li-num in flat sheets 32 inches wide, manu¬ factured by the Flax-li-num Insulating Co., St. Paul, Alinn. (7) Application: From foundation to top floor ceiling line F'lax-li-num flat sheets shall be applied to the outer side of the sheathing. Flax-li-num shall be covered with a good grade of asphalt saturated paper and furred out over studding with lath. All joints to be butted tight. Above top floor ceiling line fur with lx2’s and lay up wall. 46 Heat Insulation for Houses Heat Insulation for Houses 47 Sound Control and Roof Insulation where Outside Walls are of Brick or Hollow Tile Standard Specification No. 5-A [As Per Detail on Opposite Page, Also Page 41] SOUND CONTROL (1) Materials: Shall be Flax-li-num flat sheets, 3^" Flax-li-ntim Joist and Plate Pads and Flax-li-num flat sheets, manufactured by the Flax-li-num Insulating Company, St. Paul, Alinn. (2) Floor Deadening Application: At ceiling line build wall offset two inches in from wall line and height of joists, making top of offset full and plumb with top of joists. Place Flax-li-num Joist Pads 3^"x3"x3' on top edge of ceiling joists, also over the wall projections, to receive under flooring, which shall be laid diagonally and tight. All ceilings are to be covered with a layer of 3^" Flax-li-num applied to under side of joists. All joints to be well fitted and butted tight. Fur out with 1x2’s over Flax-li-num to receive lath and plaster. Over rough flooring lay 3^" Flax-li-num flat sheets fitted tight against Plate Pads at partitions. Finished floors to be laid directly on 3^" Flax-li-num (no furring strips). (3) Party Partition Deadening Application: Lower plates in partitions shall be placed on 3^" Flax-li-num Plate Pads projecting on each side of plate. Upper Plates shall be covered with ]/^" Flax-li-num Plate Pads. Both sides of all deadened partitions shall be covered with a continuous layer of 3^" Flax-li-num, which shall be butted tight to Plate Pads on top and bottom. Fur out with lx2’s over Flax-li-num to receive lath and plaster. Place wood headers, joist dimension, between joists on all deadened partitions. Place extra joist directly over and below deadened partitions where these parallel the joists. ROOF INSULATION (4) Materials: Shall be 1" Flax-li-num flat sheets, manufactured by the Flax- li-num Insulating Co., St. Paul, Alinn. (5) Application: Cover ceiling of top floor with 1" Flax-li-num in flat sheets applied to the under side of the ceiling joists. Flax-li-num to be run under wall offset and butted tight to outside walls. Fur out over Flax-li-num with 1x2 strips to receive lath aud plaster. SIDE WALL INSULATION See paragraphs 1, 2, and 3. Specification 11-A, page 37. For details of sound control in Fireproof Construction for floors and party walls see Plates 3, 5, and G, page 41. 48 Heat Insulation for Houses Industrial Roof Insulation E build our side walls strong and thick; we build our roofs just strong enough to be self supporting with a reasonable margin of safety. What is the modern industrial roof ? Four inches of concrete with five plies of roofing, or two inches of lumber, with a similar covering, or again steel plates, with waterproof covering. These materials make excellent roofs from every point of view except that of insulation. They are strong, watertight, and durable, but they do not keep out the cold, hold in the heat or prevent condensation. Concrete and wood both conduct heat readily, so readily, in fact, that l"of Flax-li-num is equiva¬ lent, in heat resistance, to 5 inches of wood plank¬ ing or 21 inches of concrete. Roofs cannot be built in these thicknesses, yet they must equal them in heat transmission. From a construction stand¬ point, Flax-li-num simplifies your roof problem by the insertion of a relatively thin material, light in weight, durable and lasting in quality, and equal in transmission to a much heavier roof. Again, the principle of “Convection” makes roofs the vulnerable point of construction. Con¬ vection simply means that heated air rises and seeks to escape confinement, while cold air settles toward the floor or ground. This means that the air you pay to heat, is constantly seeking ways of escape; to rise through the ceiling and roof of every building to the outside air. This constant cir¬ culation of air, which conveys heat to the roof, superheats the atmosphere at that point. Hence, even though roofs offered equal protection against heat transmission as walls, more heat would escape through roofs than through side walls. Roof insulation protects against heat loss in winter, but it also protects against heat entrance in summer. The superheating of factories, necessi¬ tating a curtailment in summer production, is eliminated by insulating the roof. This protec¬ tion against summer heat is vitally essential in one. two and three stoiy factories, where, perhaps one- third or one-half of the total floor space may be affected during the extremelv hot weather. O t/ It is an actual fact that instead of a superheated interior atmosphere, the interior temperature under roofs insulated with Flax-li-num may be held 10 to 15 degrees lower than the outside temperature. Economy through year round use of floor space is good building and good management. If space otherwise available only for storage, can be turned into more productive channels, costs must neces¬ sarily decline. Even where there is no cessation of operation in the hot weather, the output is cur¬ tailed by inefficiency in personnel due to the heat. An increase in efficiency of workers is possible simply by building into the plant the coolness of the refrigerator car. Roof insulation effects not only fuel economy, but personnel economy. It contributes to that thing for which we are striving, greater personnel efficiency, larger production, less waste, and this service, though difficult to measure in dollars and Heat Insulation for Houses 49 Flax-U-num Sheets Being Laid Out On The Boof Deck Preparatory To Mopping. cents, is perha})s as great as the winter fuel saving effected bv Flax-li-num. t. Insulation angnients the ventilating system and the two must be combined to create ideal con¬ ditions. If there is no control over the escape of heat or cold, the best ventilating system cannot The Semi-Rigid Sheet Of Flax-li-nwm Rolled Back White The Mopping Is Being Done. Xote How Flax-li-num Follows The Mop. Assuring A Firm Bond To The Roof Deck. function at anything approaching maximum ef- ficiencv. V The following specifications cover in detail, just how Flax-li-num is applied to roofs of concrete, wood and steel. There is also given on page 53 a table of transmission coefficients, fuel savings and radiation savings, which may be secured by the use of various thicknesses of Flax-li-num. Flax-li-num has many advantages as a roof in¬ sulation. First: Its semi-rigid form allows the sheets to be rolled down into the hot moi)ping closely following the mop and thus making it easy to secure a good bond by placing the Flax-li-num sheets directly into hot mopping before it has an The Built-Up Roof Applied Over The Flax-li-num — Completing The Job. opportunity to chill. Second: Flax-li-num for roof insulation should be butted tight—there being no contraction or expansion in the Flax-li-num sheets, they can be placed tightly together, thus forming a continuous sheet of insulation over the entire roof. The semi-rigid nature of Flax-li-num makes the sheets easy to handle without breaking or cracking, and there is practically no loss from spoilage. The semi-rigid nature has another advantage. The sheets easily conform to any unevenness on a roof deck, such as concrete, and eliminates any need for smoothing off such decks. Thus, when the Flax-li-num sheets are rolled down into the hot mopping you are assured of the best })ossible bond. 50 Heat Insulation for Houses Heat Transmission Values for Roofs ■■r,-:-<^.: -.0. ■ ^^ <0.; -=:-■■ ■ /° ;■ -V?r.-1 Outside Surface.So = 4.20 5-Ply Tar and Gravel Roof.C =0.40 1" Flax-li-num Insulation .C =0.28 4" Concrete Slab.C = 8.30 Inside Surface.Sr = 1 30 Development of Roof Formula 1 1 K =- K =-= 0.186 1 1 /Xo Xi \ 1 1 i ^.125 1 4 \ — + + 1 ( - + — + Etc. 1 + — + ( - + + I So Si \Co Cl / 4.2 1.3 * V .4 .28 8.3/ K = Total heat transmission per sq. ft. per hour per deg. Fahr. tem¬ perature difference. 50 = Outside Surface Coefficient. 51 = Inside Surface Coefficient. X = Thickness of material in inches. C = Conductivity Coefficient per inch of thickness per sq. ft. per hour per deg. Fahr. Insulating Values of Some Common Building Material* Material Surface and Conductivity Factors Thickness In Inches B. T. U. Transmission per sq. ft. per hr.per deg. F. temp. diff. Brick Wall. So = 3.90 9'' .36 Si =1.30 13" .28 C =5.00 18" .22 24" .18 Concrete Walls or Roof Deck. So = 3.90 2" .78 Si =1.30 3" .72 C =8.30 4" .66 6" .56 Windows. Single 1.13 Double .45 6" or 8" Hollow Tile Roof. plus 2 " Concrete plus 8" .38 Tar and Gravel Roofing 10" .36 Flax-li-num. C =0.28 14" .367 1" .245 2" .134 Magnesia Board. 1" .35 2" .21 4" .12 *Value.s obtained from Harding & Willard, U. of Penn, and U. of M inn., shown here for jmrposes of ready comparison. The data given here are taken from i-eliable sources. The heat floAV was determined by actual tests on a practical size section. These tests check, within experimental limits, the results which can be computed from the formula derived by Willard and Lichty, Fmiversity of Illinois. It is difficult to get reliable results on the coefficients S and So, therefore, only those tests which can be substantiated are given. The steam radiator emits approximately 250 B. t. u. per square foot per hour. The steam coil emits approximately 275 B. t. u. per square foot per hour and the hot water radiator approximately 156 B. t. u. per square foot per hour. One pound of ice will give up approximately 144 B. t. u. in melting. The total heat which is to be supplied per hour can be com¬ puted as follows: H = (KrC + KwW+K gG -h0.02VX) (T—To) For heat loss thru roof Hr = KrR (Ti— To) AYhere H = Total heat in B. t. u.’s of entire heated space. Hr = Total heat thru roof in B. t. u.’s. R = Roof surface in square feet. W = Wall surface in square feet. G = Glass surface in square feet. V = Volume of air in cubic feet. N = Number of air changes. N = 2 for factories, 1 to 2 for schools and public pla¬ ces.)^ to 1 for storage. Ti = Inside temperature (Breathing line). T = Inside temperature under roof. (Over 10 foot high roof, add 15 to 25% to inside temp.). To = Outside temperature. Kr = Heat transmission constant for roof. Kw = Heat transmission constant for walls. Kg = Heat transmission constant for glass. 0.02 = B. t. u. to raise 1 cubic foot of entering air 1 degree F. The temperature of the air in contact with the under side of a roof is much higher than the temperature maintained at the breathing line. It has been found liy exjieriment that fifteen to twenty-five per cent should be added to room temper¬ ature in order to have a correct rearling for temperature at ceiling. This increase has not been taken into consideration in the comjmtations on the following page, but should be applied for rooms over ten feet high. Heat Insulation for Houses 51 Chart Showing Relative Humidity Which May be Carried Under Various Roof Decks without Condensation on Their Under Surface NOTE:—All curves are based upon 70° F. dry bulb temperature. For any other appreciably different dry bulb temperature a correction should be made to the relative humiflity found by these curves. CONCRETE DECKS- No. 1—Four inch concrete slab, bare. No. 2—Four inch concrete slab, plus 5-ply roofing. No. 3—F our inch concrete slab, plus 1" Flax-li-num, 5-ply roofing No. 4—Four inch concrete slab, plus 2" Flax-li-num, 5-ply roofing. WOOD DECKS- No. 5—One and three-eighths T. & G. spruce plank plus, 5-ply roofing. No. 6—One and fhree-eighths T. & G. spruce plank plus, 1'' Flax- li-num. plus 5-ply roofing. No. 7—One and three-eights T. & (i. spruce plank plus 2" Flax- li-num, plus 5-ply roofing. No. 8—Two and three-eighths T. & G. spruce plank plus 5-ply roofing STEEL DE('KS-- No. 9—Steel deck and 5-ply built-up roof (no insulation) No. 10—Steel deck with one-half inch Flax-li-num and 5-j)ly roof. No. 11—Steel deck with 1 inch Flax-li-nnm and 5-ply roof. In homes, schools, factories, theatres or wherever a humidity to encourage the best of health or the best condition of goods is essential, it is desirable to retard, to the greatest degree, the penetration of moisture into the material used as insulation. It is just as desirable to prevent condensation upon a ceiling. This, of course, can be accomplished only by retaining a surface temperature above that of conden.sation at a given humidity .According to the Forest Products Laboratory, it is impossible to absolutely waterproof a material. It is, however, possible to retard the rate of pene¬ tration of the moisture and the prevention of coiiflensation heafls off many of the difficidties that would otherwise arise. The curves, shown on this page, determined by F. R. Shehlon & Sons of Providence, R. L, in 1917, for Textile Mills, will show the roof construction necessary to prevent condensation at a given humidity. The following illustration will show the necessity of insulation to prevent condensation. EXAMPLE: It is desired to maintain a humidity of 65% with a temper¬ ature of 50 degrees F. for provisions. The outside temperature will reach —20° F. The total temperature difference then is 70°. Now run a line per¬ pendicular to the base at 05% relative humidity, continue this line until it intercepts the 70° line. Curve 11 will give us the recpiired j)rotection. If our inside temperature is 70° F. instead of 50° as above, and the outside temperature en-20° F., we would have a heat head of 90° F. Now, with a humidity of 65%, our intersection wonld be to the riglit of curve 11 on the 90° heat head line. With this condition, it would be necessary to increase the amount of insulation to a point where the value of the roof would equal that of curve 3. There are three factors involved in these determinations, first: the out¬ side temperature; second: the “heat head” or tem{)erature difference between the outside and inside of the roof; and third; tlie relative humidity to be maintained. It is clear that where the outside and inside temperatures correspond exactly, there will be no condensation till the air reaches a satu¬ ration of 100%. The ideal insulating material would, then, support 100% humidity under any “heat head” and the “curve of the perfect insulator” shown on the chart is consequently a straight line at 100%. In protecting against condensation it is a grave mistake to figure avei-age temperatures. Even on an unprotected roof, conden.sation does not neces¬ sarily occur all the time. If, however, it occurs four or five times a year, the resulting damage may be very sev'ere. Basing conden.sation comj)utations on extremef! of temperature is, therefore, not extravagance, but common sense. This, if an extreme temperature of 20 degrees below zero is probable during the winter, then, figuring 70 degrees as the interior temperatur*' at the ceiling line (the warmest portion of the building), a “heat heafl” of 90 degrees will be a fair basis upon which to figure condensation. 'Fo insulate for an average winter temperature of, say 2() degrees above zero, in this case, would mean that whenever the temperature got below this mark, conden¬ .sation would take place. It would be poor economy and faulty construction. 52 Heat Insulation for Houses Heat Transmission of Wood Decks with Suspended Ceilings Uninsulated Insulated Flax-li-num Keyboard Plaster Base 5 Ply Built-Up Roof Roof Boards Roof Joists Suspended Ceiling Lath 86 Plaster Transmission K=.284 5 Ply Built-Up Roof Roof Boards Roof Joists Suspended Ceiling Plaster On Flax-li-num Keyboard Transmission K=.196 Insulated 1 inch Flax-li-num 5 Ply Built-Up Roof I Roof Boards Roof Joists Suspended Ceiling 1" Flax-li-num l"x2" Furring Lath 86 Plaster Transmission K—.132 Heat Insulation for Houses 53 Radiation and Heat Losses on Industrial Roofs CONCRETE DECK Without Insulation With I^-inch Flax-li-nutn With 1-inch Flax-H-num With ^-inch Flax-li-num Insulation Insulation Insulation *HEAT TRANSMISSION for a 4" concrete deck, plus 5-ply built- up roof. .557 .279 .185 .112 HEAT LOSS in B. t. ids i)er 1,000 square feet for a 40° E. difference in temoerature for a heating season of 210 days. HEAT LOSS IN POUNDS OF COAL per 1,000 square feet of roof surface for 40° difference in temperature for 210 days (available heat ])er pound of coal 6,500 B.t.u’s). 112,224,000 56,280,000 37,464,000 22,596,000 17,265 8,659 5,764 3,476 RADIATION REQUIRED for 1,000 square feet of roof when a temperature of 70° F. is maintained under roof with outside tem¬ peratures as indicated. (275 B. t. u’s per square foot of steam-coil radiation) Outside temperature 0° F. 141 71 47 28 Outside temperature -10° F. 161 81 54 33 Outside temperature -20° F. 182 91 61 37 WOOD DECK Without Insulation With I^-inch Flax-li-num With 1-inch Flax-li-num With 'J-inch Flax-li-num Insulation Insulation Insulation *HEAT TRANSMISSION for a 2" wood deck roof, plus 5-pIy built-up roof. HEAT LOSS in B. t. u’s per 1,000 scjuare feet for a 40° F. difference .380 .227 .161 .102 in temperature for a heating season of 210 days. HEAT LOSS IN POUNDS OF COAL per 1,000 square feet of roof surface for 40° difference in temperature for 210 days (available heat per pound of coal 6,500 B. t. u’s). 76,608,000 45,789,000 32,482,000 20,563,000 11,785 7,040 5,000 3,165 RADIATION REQUIRED for 1,000 square feet of roof when a temperature of 70° F. is maintained under roof with outside tem¬ perature as indicated. (275 B. t. u’s per square foot of steam-coil radiation) Outside temperature 0° F. 97 58 41 26 Outside temperature -10° F. 111 66 47 30 Outside temperature -20° F. 124 75 53 34 STEEL DECK Without Insulation With J-^-inch Flax-li-num With 1-inch Flax-li-num With s2-inch Flax-li-num Insulation Insulation Insulation *HEAT TRANSMISSION for a steel deck roof, plus 5-ply built-up roof. .94 .35 .216 .122 HEAT LOSS in B. t. u’s per 1,000 square feet for a 40° F. difference in temperature for a heating season of 210 davs. HEAT LOSS IN POUNDS OF COAL per 1,000 square feet of roof surface for 40° difference in temperature for 210 days (available heat per pound of coal 6,500 B. t. u’s). 189,504,000 70,560,000 43,545,600 24,620,000 29,154 10,856 6,699 3,790 RADIATION REQUIRED for 1,000 stiuare feet of roof when a temperature of 70° F. is maintained under roof with outside tem¬ peratures as indicated. (275 B. t. u’s per square foot of steam-coil radiation) Outside temperature 0° F. 239 89 55 31 Outside temperature -10° E. 274 102 63 36 Outside temperature -20° F. 308 115 71 40 *B. t. u. per square foot per hour per degree F. temperature difference. 54 Heat Insulation for Houses Detail No. 1 5 Ply Built Up Roof Roofing Composition, Mopping Flax-li-num Mopping Priming Concrete Detail No. 2 5 Ply Built Up Roof Roofing Composition, Mopping Flax-li-num Water Proof Paper Roof Boards Detail No. 3 5 Ply Built Up Roof Roofing Composition, Mopping Flax-li-num Roof Boards Heat Insulation for Houses 55 Heat Insulation for Flat Roof Decks Standard Specification No. 2-A [As Per Detail on Opposite Page] CONCRETE DECK (Detail No. 1) (1) Roof Deck: (Concrete): Shall be finished smooth, without depressions that could hold water, properly graded to drains, and thoroughly dry and clean. (2) Materials: Shall be 1" Flax-li-num, manufactured by the Flax-li-num In¬ sulating Company, St. Paul, IVIinn. A good grade Roofing Comjjosition or Cement shall be used for all moppings. Roofing as specified elsewhere. (3) plication: Where asphalt roofing composition is used prime concrete surface, using at least one gallon of priming per 100 stpiare feet. Where coal tar pitch roofing composition is used priming not necessary. Mop thoroughly over deck and lay Flax-li-num into hot mopping, pressing down into mopping in workmanlike manner. Butt all ends tightly together to insure proper insulation at joints. Mop over Flax-li-num thoroughly and lay roof over hot mopping. WOOD DECK WHERE EXCESSIVE CONDENSATION IS A FACTOR (Detail No. 2) (4) Roof Deck: (Wood): Shall be well seasoned, narrow width lumber, prop¬ erly nailed and free from wide cracks, knots and imperfections. Roof surface shall be smooth, clean and properly graded to outlets, without depressions which could hold water. Cant strips shall be applied at fire walls and elevations. (5) Materials: Shall be 1" Flax-li-num, manufactured by the Flax-li-num In¬ sulating Company, St. Paul, Minn. An approved Roofing Composition shall be used for all moppings. A thorouglily saturated water-proof felt shall be used under the Elax-li-num. (6) * Application: Lay one thickness of water-proof felt, overlapping joints at least 4 inches. Lay Flax-li-num sheets over water-proof felt, butting ends and sides carefully to insure a continuous sheet of insulation. Run Flax-li-num to all walls and fit tightly around all openings in roof, nailing Flax-li-num every 12 inches along edges with large head roofing nails. Mop entire surface thoroughly, using sufficient roofing com])osition to water-proof insulation. WOOD DECK UNDER NORMAL HUMIDITY CONDITIONS (Detail No. 3) (7) Roof Deck: Same as Detail No. 2. (8) Materials: Flax-li-num mopping and roofing same as Detail No. 2. Omit water-proof paper under Flax-li-num. (9) * Application: Same as above. *Iniportant: See Paragraph 4, Page .57. 56 Heat Insulation for Houses The need of Flax-li-num on steel decks is so evident that it need hardly be argued. In fact, on any building that is to be heated (not taking into consideration any coal savings), enough is saved in the heating plant to more than pay for the insulation; in other words it is cheaper to build a building with it than without it. For example: the transmission on a steel deck with three-ply Built-Up Roof is, .94 B.t.u’s per hour, per square foot, per degree temperature difference. Taking a temperature difference of 70° F. (70° under roof and 0° outside) and proportioning the radiation for this type of roof without insu¬ lation, the amount of direct radiation neces¬ sary to offset the heat loss for 1,000 square feet of roof is 239 feet. With one-inch Flax- li-num the transmission would be .210 B.t.u’s per hour, per square foot per degree temper¬ ature difference and the radiation necessarv for 1,000 square feet of roof is 55 feet, or a saving of 184 feet of radiation on each 1,000 square feet of roof area. Heat Insulation for Houses 57 Heat Insulation for Steel Deck Roofs Standard Specification No. 14-A [As Per Detail on Opposite Page] (1) Boof Deck: Steel properly graded to drains, and thoroughly dry and clean. (2) hisulating Material: Shall be 1-inch Flax-li-num manufactured by the Flax-li-num Insulating Company, St. Paul, Minn. A good grade roofing cement shall be used for all moppings. Roof¬ ing as specified elsewhere. (3) Application: Mop thoroughly over steel deck with Standard Grade Roof Composition and lay Flax-li-num into hot mopping, pressing down into mopping in workmanlike manner. Butt all ends tightly together to insure proper insulation at joints. Run Flax-li-num tight to all walls and butt tightly at all openings in roof. Mop over Flax-li-num thoroughly and lay roof into hot mopping. (4) Important: Flax-li-num must be laid into roofing composition / / / Flashing and Cut-off Detail for Insulation Under Built-up Roofs A This detail covers the application of insu¬ lation in connection with specifications 2-A and 14-A. This plate shows the wood strip laid to all walls for nailing flashing. The cut-off should be used to seal off the Flax- li-num in areas of approximately 100 square feet, and should also be used to close up the job at the end of work for the day. ''///Z wood strip cut-ofi immediately after mopping, or composition will become hard before sheets are laid. Do not lay more Flax-li- num than can be covered in a day. All edges or expos¬ ed parts of Flax-li-num to be covered with cap sheet mopped to deck, and reopen¬ ed when work is resumed. Run insulation tight to all walls and butt tightly at all openings in roof, flashing as specified elsewhere. 58 Heat Insulation for Houses Flax-li-num Test Data Ill considering an insulating material there is one imjiortant factor that should be well noted, that is, the distinction between thermal conductivity and thermal transmission. These values differ and the one can not substitute for the other. The reason for jiaying close attention to the differences is, that insulating materials perform differently under dif¬ ferent methods of application and the test data should be apjilied in a manner that will give correct values for the entire wall or roof unit when com¬ pleted. Conductivity (’onductivity represents the number of B. t. u.’s that will jiass through one inch of thickness of an insulating material, per scpiare foot, per degree F. jier hour. It should be noted that the heat flow here is through the material only and is a surface to surface measurement. (See hgure 1.) Ti 'ansmission The term transmission as used here represents the number of B. t. u.’s that will pass through one ineh of an insulating material per scpiare foot, per degree F. jier hour, and includes the surface re¬ sistances. in addition to the thermal conductivitv.* __ K- (See hgure t.) It will lie noted that the transmission factor is lower than the conductivitv factor. Thus, the insulating value of a material so applied as to take advantage of the surface resistances is better than though the same material were apjilied so that sur- faee resistances are eliminated. Methods of Testing' Thermal conductivitv is arrived at bv the hot jilate method of testing. Transmission is arrived at by the hot box method, as well as by computa¬ tions from hot plate results. *The term transmission is also used to represent the total heat travel through a comiionnd wall or roof made n]) of va¬ rious hnilding materials and air s])aces. The illustrations of temperature gradients here shown, (Figures I and 't) plainly indicate the differ¬ ence in results obtained bv the hot box and the hot t. plate methods of testing. Hot Box Data--Tra7is7nission When Flax-li-num is applied between studdings, midway between the inner and outer wall units, or on ceilings, with furring strips, giving air spaces on both sides of the insulation, in accordance with the specifications shown on pages 31, 33, and 35, the transmission factors obtained by the hot box method are used. For the standard thicknesses of Flax-li-num these values are as follows: yT Flax-li-num .37 V Flax-li-num .24 The above transmission co-efficients are in ac¬ cordance with the tests as published in Bulletin #3, Engineering Department of the University of Minnesota. Hot Plate Data--Co7iductivity When Flax-li-num is so applied that the surface resistances are eliminated, such as is the case when the material is used for roof insulation, mopped down to the deck and covered with a built-up roof. Figure I Wi i : Cold Plate e i m w Hot Plate $ r s>Wi.^ m Hot Plate Test for Conductivity “C” Figure 11 Hot Box Test for Transmission “K” Heat Insulation for Houses 59 the conductivity values obtained by the hot plate method are used. Hot plate tests on Flax-li-uum, as })ublished by the United States Bureau of Stand¬ ards, give a conductivit}" co-efficient of .3^2 per inch of thickness. Computing in accordance with the method approved by the Bureau for determining the actual conductivitv of commercial thicknesses, gives the following values for the standard thick¬ ness: Flax-li-num .56 1' Flax-li-num .28 All of the computations for wall sections and roofs covered in this Bulletin, are based upon the proper application and the proi)er co-efheient as outlined above has been used. Caution: When considering wall or roof con¬ struction the transmission or eonduetivitv factors t for the various units should be computed on the actual thickness in which each unit is to be used. Care should be taken not to misinterpret test data of Laboratories which are always given upon a unit thickness and not upon the thickness of the mate¬ rial as actuallv manufactured and used. Flax-li-num—Standard Items Sheet Sizes, Sqjfare Footage and Wei ght Thickness I ^orin Width Length Scj. Ft. i)er Sheet 34 Inch. . Flanged .1634 Inches . 8 Feet. .11.00 34 Inch Flanged 1634 Inches 9 Feet 12.37 34 Inch . . .Flanged .1634 Inches .10 Feet. .13.75 34 Inch . . .Flanged . 2434 Inches . 8 Feet. .16.33 34 Inch Flanged 2434 Inches 9 Feet 18.37 34 Inch . . .Flanged . 2434 Inches .10 Feet. .20.41 34 Inch . . .Flat... . .32 Inches. . . 8 Feet. .21.33 34 Inch Flat 32 Inches 9 Feet 24.00 34 Inch . . .Flat... . .32 Inches . . .10 Feet. .26.66 34 Inch. . .Flat... . .32 Inches . . . 8 Feet. .21.33 34 Inch Flat 32 Inches 9 Feet 24.00 34 Inch. . Flat. . . .32 Inches . . .10 Feet. .26.66 1 Inch. . . Flat. .32 Inches . . . 8 Feet. .21.33 1 Inch Flat 32 Inches 9 Feet 24.00 Ftanged Ftax-ti-num Sound Controt Headers 34 Inch. ... Flanged .1634 Inches . 4 Inches. . 0.46 34 Inch Flanged 1634 Inches 6 Inches 0.69 Ftax-ti-num Sound Controt Joist Pads 34 Inch. . . . Flat... . 3 Inches.. . 3 Feet. . 0.75 Ftax-ti-num Sound Controt Ptate Pads 34 Inch. . Flat.... . 4 Inches.. . 3 Feet. . 1.00 34 Inch Flat 6 Inches 3 Feet 1.50 Ftax-li-n u m Keyhoa rd Furnished in two sizes: 36" x48" and 36" x 32" (one-half of each size should be specified). Actual weight of Flax-li-num (not to be confused with shipping weights, which vary with mode of shipment). 34 Inch— 40 lbs. per hundred square feet 1 Inch—115 lbs. per hundred square feet 34 Inch— 60 lbs. per hundred square feet Keyboard—125 lbs. per hundred s([uare feet Heat Insulation for Houses library ' UHlVERSlTfi F6| VALUE OF K IN B. T. U. PER SQUARE FOOT OF EXPOSED SURFACE PER DEGREE FAHRENHEIT PER HOUR FLAX-LI-NUM RADIATION CHART Based on Actual Heat Loss Through Building Construction 0.60 0.58 0.56 0.54 0.52 0.50 0.48 0.46 .34 0.32 0.30 0.28 0.26 0.24 0.18 0.16 0.14 0.12 0.10 0.02 Engineering Department FLAX-LI-NUM INSULATING CO. St. Paul, Minnesota 4 Reference Number 0) T) C CO OKd. VALUE OF X ■ 70—(—20) ’ Follow Reference line 1.73 to the intersection of horizontal line 0.27 and then drop vertically to bottom of chart and read number of square feet of wall surface per square foot of radiation, which -= 274.6 sq. ft. of rad. required to offset heat loss through wall. For ceiling follow Reference line 1.73 to inter¬ section of horizontal line 0.35; then drop verti¬ cally to bottom of chart and read number of square feet of radiation which is 4.8, whence 187.5 sq. ft. of rad. required to offset heat loss through ceiling. (2) For glass follow Reference line 1.73 to horizon¬ tal line 0.62, then drop vertically to bottom of chart and read number of square feet of glass surface per sq. ft. of radiation, which is 2.6 430 whence 165.4 sq. ft. of rad. required to offset heat loss through glass. For infiltration with Reference number 1.73 one square foot of radiation for every 94.5 cubic feet of air. (See table at left.) Then with num¬ ber of air change of 1 per hour we have = 171.4 sq. ft. of rad. required to offset heat loss due to infiltration. Table for comput¬ ing radiation to offset infiltration W WK WZ K Total Radiation required = 274.6+ 187.5-)- 165.4 + 171.4 = 798.9 square feet. Add 10 per cent for exposure. Total Radiation =878.8 square feet. 1 2 3 4 5 6 7 8 9 10 15 25 3U 49 59 NO. OF SQUARE FEET OF EXPOSED BUILDING SURFACE PER SQUARE FOOT OF RADIATION 30 1 ) Reference Number = I ^ ^ Room Temp. - Outside Temp. Reference Number “Curve Number. EXAMPLE; — Given room temp. 70° F, out¬ side temp.—20°F, Hot Water radiation installed ' to give off 156 B. t. u. per sq. ft. of radiating sur¬ face under above conditions. House has 1730 sq. ft. of wall surface. Kw = 0.27. Ceiling surface is 900 sq. ft. with Kc = 0.35. Glass surface is 430 sq. ft. with Kg = 0.62. Cub¬ ical content is 16,200 cu. ft. SOLUTION;— Reference Number =; 'y^'sAfr /Sms 70 ... ■■ ’ ,*> ««n: •^ >^-;^-'i A>, v:W-v- ■ hjt ^-. - :;A;tiv 5';? sv-'/■!' ■•’•h t- w& '(\}y sS-. :f. r.^Vj>. 5 r J ' ^h- -- •' ' / A^."* • *•■ ..•'c* : ••■/’■'.•.■'• '.A*T, ’'i..'. ■ ■• . tv, - / K'' -' 'C ••'?/J. 4 ' ■!> ..v-; ’> v i.' V ■' ? • i i- ' i - ;• s..-' •• ■?...•>'. V’:^;»itSncS •V---.: . .V'r^-A --V.V/’. ■' ;._, Ay '-^ a'ss. ■ 1. ■■"■."