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.180 CHAPTER 9 1951 Guide 'Table:-2: 'Conductivities (k) and Conductances (C) op Building and Insulating Materials--Concluded These constant* are'expressed in Btu'per (hour) (square foot) (Fahrenheit degrees temperature difference.) Conductivities (k) are per inch thickness and conductances (C) are for thickness or construction stated, not per inch thickness. - Matebxal '; \i ! Description ! o Conduct- t> O PS Q~ PS IV1TT OB Conduct* ancb 1 Resistance n Per Inch Thick- i: sw 5- 3a (O Thick ness ness Listed 3 o g G) G). Q S INSULATING MATE RIALS--(Continued) Chemically treated hog hair between kraft paper and 7.70 Hair felt between layers of 11.00 Kapok between burlap or 1.00 Stitched and creped expending fibrous blanket... 1.50 Paper and asbestos fiber with emulsified asphalt 4.2 0.875 71 75 90 70 94 72 6.25 90 Cotton fibers 4.50 90 Short Staple Linters, 2.45 90 . .... Fireproofed:.................... 1.60 90 0.85 90 0.65 90 Felted cattle hair..................... 13.00 90 !t : t: 11.00 Felted hair and asbestos...; 7.80 Ground paper between two 90 90 layers, each | in. thick made up of two layers of' kraft paper (sample I in. 12.1 . 75 4.5. , See Table 1, Section C.......... - - Insulating Board. ...... (; ; : . -. i j : i > 'f Made from sugar cane fiber.. 13.5 15.00 Made from exploded wood fibers........................................ 17.90 Made from hard wood fibers: 15.20 Made from wood fiber....... 15.90 15.00 Made from wood fiber........... 8.60 Made from wood fiber......... 15.20 Made from wood fiber........... 16.90 Made from licorice root........ 16.1 4 in. insulating boards with out special-finish^ (eleven 16.5 to 21.8 1 in. insulating board0.,........ 13.2 70 71 .78 70 72 70 52 72 90 81 90 -- -- 1.90 75 1.60 75 \ Fibrous material made from ! dolomite and silica............. 1.50. ^ 75 Fibrous material made from' 9.40 103 Redwood bark......................... 3.00 90 5.00 75 Glass wool fibers 0.0003-in. to 0.t>06 in. in diameter.... 1.50 75 Granular insulation made |.: from combined silicate oflime and alumina..,....... 4.20 72 See footnotes on firat page of Table 2. 0.28 0.25 0.24 0.27 -- 0.28 0.24 0.25 0.24 0.24 0.26 0.29 0.30 0.26 0.28 _ _ -- -- -- -- -- -- __ 0.40 0.27 - 0.33 0.33 - ___ 0.32 0.32 0.33 0.33 0.33 0.29 0.33 0.34. 0.34 -- -- -- _ -- -- -- -- 0.33 to 0.40 0.34 0.23 0.24 -- -- -- __ __ 0.27 0.27 0.31 0.26 - -- __ 0.27 -- 0.24 - 3.57 4.00 4.17 - 3.70 3.57 4.17 4.00 4.17 4.17 3.85 3.45 3.33 3.84 3.57 3.70 . - 3.03 3.03 3.12 3.12 3.03 3.03 3.03 3.45 3.03 2.94 2.94 3.03 to 2.50 2.94 4.35 4.17. 3.70 3.70 3.22v 3.84 3.70 4.17 (3) (3) a) -- (3) __ 0) (3) -- -- <11 (1) 1) -- -- __ -- ?! fl) (1) 0) __ 0) a; < - -- -- -- -- _ -- -- - -- (3) (3) SI (3) to) (8) (1) (3) -- a) -- -- (4) __ __ (3) (3) C3) (1) -- __ (1) (3) -- (3) - (3) Heat Transmission Coefficients of Building Materials 181 Table 2. Conductivities (k) and Conductances (C) of Building and. 1" Insulating Materials--Concluded . That eonstania ore eepreeeed in Btu per (hour) (upturn foot) (Fahrenheit de/pee temperature difference.) 1 asse c^con4uctivmeM (fc) are per inch thickness and conductances (C) are for thickness or ^ uulMMfcM ofntael fief tneA (AieAnHl Matebxal Description fap a0 Conduct `o Gad ivity ob Conduct-* Resistance a ANCB 10, *3 1b m% H Per For Inch Thick (*> (O Thick ness ness Listed O I2 a* wQ S /1\ /1\ B KcJ 'D < INSULATING MATERI ALS--(Continued) Loose Fill Type................. --(Continued) Expanded vermiculite......... Expanded vermiculite, par ticle size------3 + 14.......... Regranulated cork about A in. particles...................... Hand applied , granular mineral wool 2 in. to 6 in. thick, horizontal posi tion6. No covering.......... 4 in. machine blown granu lar mineral wool, horizon tal position6. No cover ing.................................... Rock wool........................... 6.2 8.10 6.05 to 7.13 5.74 10.0 0.48 0.32 90 0.31 0.30 to 0.33 0.30 90 ^ 0.27 - Slab Insulations................. Corkboard, no added binder. 14.0 Corkboard, no added binder. 10.6 90 90 Corkboard, no added binder. 7.0 90 Corkboard, no added binder. 5.4 90 Corkboard**.......................... 8.7 -- Corkboard, asphaltic binder. 14.5 90 Chemically treated hog hair with film of asphalt.......... 10.0 75 Sugar cane fiber insulation blocks encased in asphalt membrane........................ 13.8 . 70 Made from shredded wood- and cement....................... 24.2 72 --Made from shredded wood and cement0..................... 29.8 0.34 . . 0.30 -- 0.27 -- 0.25 .-- --0.29 -- 0.32 0.28 0.30 0.46 --0.77 2.08 3.12 3.22 ' 3.33 to 3:03 3.33 3.70 2.94 3.33 3.70 4.00 3.45 3.12 3.57 3.33 2.17 1.30 See footnotes on first page of Table 2. (i) (3) SI - SI -- (1) --. -- -- ((/ilt))\ a)-- (4) 0) -- 0) 0) (4) ing. For increases of moisture content exceeding about 6 to 12 percent, the conduc tivity of frozen soil becomes progressively greater than that of the unfrozen soil. Effect of Density. Density affects the thermal conductivity of - a 'soil in about the same manner for all soils, at any moisture content, and for either the frozen or un frozen condition. On the average, each one pound per cubic foot increase in dry density increases the thermal conductivity by about 3 percent. Effect ofMoisture. An increase in moisture content, up to the point of saturation, causes an increase in thermal conductivity. The rate of mcrease is indicated by the following values. Average conductivities;-in Btu per (square foot) (hour) (Fahren heit degree per inch), of four sands at a density of 110 lb per cu ft were: 6.8 at 2.5 percent moisture, 8.9 at 5 percent moisture, 11.2 at 10 percent moisture, jive soils of a fine texture at a density of 100 lb per cu ft, gave average conductivities of 6.7 at 10 percent moisture, and 9.5 at 20 percent. Thus, the doubling of moisture con tent within -the ranges cited increases the conductivity by approximately 30 or 40 percent. At higher moisture contents the percentage increase would be less.- - Effect of Soil Characteristics. The thermal conductivity of the soil, at a given density and moisture content varies in general with the texture of a soil, being rela tively high for coarse-textured soils and relatively low for fine-textured soils. .The mineral composition of the soils also affects the conductivity. Quartz tends to give high values, whereas minerals such as plagioclase feldspar and pyroxene, which are constituents of basic rocks tend to give low values of thermal conductivity. These points are illustrated by the values in Table 3 which lists seventeen'soils in approxi mate order of their magnitude of thermal conductivity from greatest to least for seven different density-moisture content conditions. Some of the values in .this