Document 8R4vOVpKodeMrkxBGY0jpBbZm

ir American Society of Heating and Ventilating Engineers Guide, 1934 Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulations Tests Conducted at the U. S. Bureau of Standards.P Insulation Tests Based on Samples Submitted by Manufacturers Note.--The coefficients in Tables 2-7, inclusive, are expressed in Btu per hour per square FOOT. PER 1 DEC F, PER 1 IN. THICKNESS UNLESS OTHERWISE INDICATED. Description Density (Lb per Cu Ft) Mean Temp (Dbg Fahr) CONDUC- TIVITY (k) OR Conduc tance (O Asbestos WoodAsbestos Mill BoardBalsam Wool*............ . . Pressed asbestos__________ ________ _____ . Chemically treated wood fiber be- 123.0 60.5 86 0.84 Cabots Quilt*Cabots Quilt*.. Celotexl._______ Corkboard.. Corkboard (Eureka)...... Dry Zero*_________ ____ Eagle Insulating WoolFibrofelt*_________ ____ Flaxlinum*........................ Gyplap........ ....................... Hairinsul*.. Hairinsul*-- Hair Felt*-- Hair Felt*Insulex or Pyrocell... Insulex or Pyrocell.. Insulex or Pyrocell.. Insulex or Pyrocell.. Insulite.--................... Linofelt*__ --........... Lith_____________ ___ Magnesia (Rigid)--. Plaster.. Regranulated cork.. Rock cork............. .... Rock wool-- Rock wool-- Rock wool_ Sawdust___ Shavings.. Sheetrock-___ Thermofelt*..'. Thermofelt*__ Thermofill*...... Thermofill*.__ Thermofill*__ Torfoleum____ Eel grass between Kraft paper--........... Rigid insulation made from sugar cane fiber... . Pure; no added binder................................ Kapok between burlap or paper______ Flax and rve fiber Gypsum between layers of heavy paper (H in. thick)___________________ 50% hair; 50% jute._................................... Felted cattle hair Felted cattle hair......... .............. ;................... Cellular evnsum--dry Cellular gypsum--dry.................................. Cellular gypsum--dry.......................... ...... Cellular gypsum--dry Rigid insulation made from wood pulp.. Flax fibers between paper Rock wool, flax and straw pulp with binder......................... ..................................... 85% magnesia, 15% asbestos................ . Gypsum.... ............................... ..................... About in. particles ............................ Rock wool block with binders._________ Fibrous material, made from rock......... Fibrous material, made from rock Fibrous material, made from rock......... Fibrous material, made from rock......... 3.4 13.2 14.0 10.6 7.0 1.0 9.4 13.6 13.0 53.5 6.3 6.1 13.0 11.0 30.0 24.0 18.0 12.0 16.9 4.9 14.3 19.3 46.2 8.1 14.5 10.0 14.0 18.0 21.0 Gypsum mixed with sawdust between layers of heavy paper (0.39 in. thick) Jute and asbestos fibers, felted. Hair and asbestos fibers, felted............ Dry, fluffy, flaked evDSum....... ................. Dry, fluffy, flaked gypsum......... ............... Dry, fluffy, flaked gypsum....... ................. Peat moss compressed into sheet form 60.7 10.0 7.8 34.0 26.0 19.8 10.2 s 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 86 86 90 77 90 90 90 90 90 90 90 90 90 90 91.5 0.25 0.34 0^27 0.24 0.32 0.31 2.60* 0.26 0.26 0.26 1.00 0.77 0.59 0.44 0.34 0.28 0.40 0.51 2.32* 0.31 0.33 0.27 0.28 0.29 0.30 0.71 . 3.60* 0,37 0.28 0.60 0.52 0.35 0.29 Woods: Balsa wood.... Balsa wood.__ Balsa wood.__ Cypress______ Maple.. Mahogany.___ Virginia pine. White pine..--. Across grain........................................................ Across grain. ....... Across grain Across grain. .................................................... Across erain Across grain....................................................... Across grain Across grain......................... ................. --........ 20.0 8.8 7.3 28.7 44.3 34.3 34.3 31.2 90 0.58 ' 90 0.38 90 0.33 86 , 0.67' 86 1.10 86 0.90 86 0.96 86 0.78 In addition to the conductivity values for the authorities listed, considerable work of importance per taining to the heat transmission of various types of construction and materials has been done by. the late Prof. John R. Allen and the late Prof. A. J. Wood of the Engineering Experiment Station of Pennsylvania State College. * *For thickness stated or used in construction, not per 1 in. thickness. *Not compressed. . The conductivity of plaster varies with the composition. Note range of values, from 2.32 to 8.0. On account of the comparatively high conductivity of plaster and the fact that it is seldom applied more than fi in. thick, this material does not appreciably affect the over-all transmission of a construction, excepting in the case of thin uninsulated walls. *See Chapter LX, by Chas. H. Herter of the Report of the Insulation Committee, A.S.R.E., Annual .Meeting 1922, Revised to 1924, entitled Heat Transmission of Insulating Materials fora more compre hensive collection of heat transmission data relating to building and insulating materials. 76 Chapter 5--Heat Transmission The majority of the conductivities and conductances of the building materials and insulations given in Tables 2, 3, 4, 5 and 6 were determined by the hot-plate method of testing2. Attention is called to the fact that conductivities per inch of thickness of materials or insulations do not afford a true basis for comparison, although they are frequently used for that purpose. Correct comparisons should take into consideration many different factors, including conductivities or conductances, thicknesses installed and manner of installation, while the selection of an insulation should also give consideration to structural qualities, as well as material and application costs. Fire, vermin, and rot resistance are other im portant factors to be considered when comparing materials. At present there is no universally recognized method of rating insulations. Con ductivities and conductances of building materials and insulations are useful to the heating engineer in determining over-all coefficients of heat transmission of walls, floors, roofs .and ceilings. Table 3. Conductivities (*) and Conductances (C) of Building Materials and Insulations Based on Tests Conducted at the University of Illinois, By A. C. Willard, L. C. Lichty and L, A. Harding P Material Description Density (Lb per Cu Ft) Mean Temp (Deg Fahr) CONDUC- TIVITY (k) OR CONDUC-.: TANCE (Cj Mortar bond and dry conditions______ 48.3 20.4 132.0 2 in. hollow clay tile, M in. olaster both sides.________ 4 in. hollow clay tile, K in. 6 in. hollow clay tile, M in. Wood (Fir. onesurface finished)-- ......... Cement__________________ ____________ Built-up bitumen and felt, gravel or slag surfaced.......................................... - Built-up bitumen and felt, gravel or slag surfaced --. ....... Across grain.................................................. 140.0 9.7 120.0 127.0 124.3 13.5 -- 33.4 110 110 100 110 - 110 100 105 110 -- -- -- 0.29 0.48 4.00 5.00/ 8.00/ 8.30 0.32 1.00* 0.60* 0.47* 0.51 8.00* 1.325* 5.30--* 1.00 ln addition to the conductivity values for the authorities listed, considerable work of importance per taining to the heat transmission of various types of construction and materials has been done by the late Prof. John R. Allen and the late Prof. A. J. Wood of the Engineering Experiment Station of Pennsylvania State College. *For thickness stated or used in construction, not per 1 in. thickness. ^Calculated from 2 in. tile tests. /Cement mortar and stucco assumed same as cement plaster. *Roofing. 0.15 in. thick (1.34 lb per sq ft), covered with gravel (0.83 lb per sq ft), combined thickness assumed 0.25. `The conductivity of plaster varies with the composition. Note range of values from 2.32 to 8.0. On account of the comparatively high conductivity of plaster and the fact that it is seldom applied more than X in. thick, this material does not appreciably affect the over-all transmission of a construction, excepting in the case of thin uninsulated walls. , /Recommended value. See Healing, Ventilating and Air Conditioning, by Harding and Willard, revised edition. 1932. ?See Chapter LX, by Chas. H. Herter of the Report of the Insulation Committee. A.S.R.E., Annual Meeting, 1922. Revised to 1924, entitled, Heat Transmission-of.Insulating Materials for a more compre hensive collection of heat transmission data relating to building and insulating materials. *See Standard Test Code for Heat Transmission through Walls (A.S.H.V.E. Transactions, Vol. 34, , 1928). See also Chapter 40. 77