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126 CHAPTER 6 1949. Guide Table 4. Conductivities (fc) and Conductances (C) Used in Calculating Heat. Tbansmission Coefficients (J7) in Tables 6 to 18' These constants are expressed in Btu per {hour) {square foot) {Fahrenheit degree temperature difference). Conductivities (k) are per inch thickness and conductances (O are for thickness or construction stated, not per inch thickness. MATERIAL DESCRIPTION AIR SPACES BOUNDED ST O&DtKABT imtwtim Bounded bt aluminum ron,__ I Vertical*. 4^ Id. or more In widthTM Vertical0. % in. or more In width.. CoNDucrmrr OB Conductance <*) (O Rbsibtancb Per loch, for ~ ThickoesBj ThUicrkto3o/M (i) (*). MO 031 0.46 2.17 EXTERIOR FINISHES (Frame Walls) Buck Veneer.. Stucco (1 in.)... 1 4 in. thick (nominal) Wood Shingles- Yellow Piow Lap Siding___ 0.44 1.28 0.78 138 0.78 INSULATING MATERIALS Aluminum Fen. Bats and I CORXBOlBD-- Insulating BnARn,, Mineral Wool,.,,,. , Vermiculitb-- See Air Spaeea.. Made from mineral or vegetable fiber or animal hair, enclosed or open Pore, no added binder--________ Vegetable fiber. Fiber made from rock, slag or gl--_ RrpatyifH____ 003330 037. 0.48 .3.03 3.70 INTERIOR FINISHES Composition Wallsqabd-- GTPSUM PtAflntw X intoKia. thick- Gtpsum Gypsum Board ($4 m.),, Lath (Si in.) andFuet^J plain or decoratedHaster thickness imnuri Vi in.. iInsulating Board (W in.). Plain or decorated--._______ Insulating Board Lath (j in.) and Plantku Plaster thickness assumed M in., Inbulatino Board Lath (1 in.) and Plastbh Metal Lath and Plaster- Pltwood (H n.),_________ Wood Lath and Plastbr_ Plaster thickness assumed H ini, Hester thickness ftgmrrwri in. Plain or decorated.--...- __MASONRY MATERIALS ... Brick-- Brick. Cement Mortar . 3 in. Clat the (bollow)-- 4 in. Clat ma (hollow)-- 6 in. Clat tils (bollow)8 in. Clat tilz (hoiaow)-- 10 in. Clat tils (hollow).. 12 nr. Clat tor (hollow)-. 16 nr. Clat tils (hollow)-. Concrete__________ _______ ConcreteTM 3 nr. Concbbts blocks-- 4 nr. Concrete blocks-- 8 in. Conchxtb blocks.. 13 nr. Concbbts blocks.__ 8 nr. Concerts blottr__ 812 in. Conckstb blocks.__ in. Concrete rhottr 12 in. Concbbts blocks.!.-- Gtpsum rasa concrete_______ 3 nr. Gtpsum rn. 4 nr. Gtpsum tils______ Stucco-- Tils and Tebrazzo-- Stone.______ _______ " Adobe, assumed 4 in. tMA Common, assumed 4 in. thick-- Face, assumed 4 in. thick_____ Light weight aggregate6............. SiManudi aianudu gravis aaggggrreeggaavte........ Hollow, cindez aggregate. HMVoUlloUwW, cViUnWdeRr aggnwfttf. RHuvoQu/uojwi/i, Mg&rioaTv.cei*l aggregate.-- Hollow, grave! aggregate___ Hollow, cinder aggregate--........... ....... ..... Hollow, cinder aggregate-__ ______ HoQow, light weight aggregate6 Hollow, tight weight aggregate6.__ __-- 87H per cent gypsum and 12M per cent wood chips........ .............. --..... . Hollow__ ...--------- ----------------- -------.------Hollow---------- ------------- ----- --:-------- ----- For flooring.---------------------------------- ---.... 0.50 330 3.70 2.4. 0.66 0.60 oil 4.40 2.12 230 "fi0 12.00 1.25 230 Tis 1.00 0.64 00.3630 0.40 0.31 138 IJ00 1.00 0.80 0.60 033 030 0.47 1230 12X10 1230 0.61 .0.46 0.08 0.08 0.27 0.42 132 1.67 3.18 0.23 0.47 0.40 M2. a0.4830 wi 1X0 137 1.67 1.72 2.50 0.78 ,00- 130 1.25 1.66 138 2X10 2.13 1.64 2.18 but mComndousct ctaansecseivtaisluseusfffiocriehnotrlyizaocnctaulraatier stopaucseestdheepseonmdeovnawluheestfhoerrhthoerisheoaStaflolZwfoisr USDwaSrd or.dZoim,vnirA ' Expanded slag, burned clay or pumice. ; - . Heat Transmission Coefficients of Building Materials - 127 _ ot.e 4 Conductivities (fc) and Conductances (C) Used ln Calculating Heat I able ",j.RANaMIESIOfI_ Coefficients (/) in Tables 5 to 18--Concluded '*...... ' '---------- . iPr,h*,n)>rii tUnree temneratwre difference). -- ----------------- ----------------------- MATERIAL DESCRIPTION CONDUCnVTTT Conductance . < n Resistance Per Inch Far Thickness Thickness listed a) (?) ROOFINQ MATERIALS ^MiesTOS Shingles------------ Astasia Shingles------- ------------------RuiLt-ut EoonKQ ----- ------------------ Assumed thickness M Id.------------ - Heatt Roll Rooting----------- ---- Assumed M ------------------------------------------SiatB ' ..--.--***--* -- -- IOjOO* 6.00 6.50 333 630 20.00 133 -- -- sheathing Insdieting Board (jMi tit.)------------Plywood (% in.)-...-----------------?ib ob Yellow Pins (1 in.)------------- Actual thickness _ in------.......-- ------------ -- SURFACES Ordinary noiwcfieetive materials, vertical-- _ 15 MPB WIND VELOCITY-------------------- Ordinary non-reflective materials, vertical-- WOODS F(B SHEATHING (1 IN.) BUILDING PAPER and Yellow Pine lap siding------- 1.15 030 232 0.42 2.56 1.02 036 ___ ,,, __L_ -- 1.65 ___ 6.00 030 037 135 0.17 0.15 0.28 0.15 0.05 0.78 ` 035 0.39 1.16 061 0.17 2.00 -- sion Vi of the insulated construction may be compared with the corre sponding coefficient U without insulation. Attention is called to the necessity of applying the insulating material in accordance with the manu facturer's specification. The engineer must carefully evaluate the eco nomic considerations involved in the selection of an insulating material as adapted to various building constructions. Lack of proper evaluation, " 1----------------- unoo+iefopfiirv fPSllltS. Computed Heat Transmission Coefficients Computed over-all heat transmission coefficients of many common types of building construction are given in Tables 5 to 18, inclusive, each coeffi cient being identified by a serial number except in Table 18. For example, the coefficient U of a brick veneer, frame wall with wood sheathing and J-inch of plaster on gypsum lath is 0.27 (Wall No. 28-C in Table 5) and with 2-inches of blanket or bat insulation the coefficient would be 0.097 (No. 49-B in Table 6). In the analysis of any wall construction for the purpose of calculating the over-all coefficient of heat transmission U, it is first necessary to deter mine the paths of heat flow; that is, whether they are parallel or series, or a combination of both. This is in accordance with the basic laws of heat transfer, which state that in parallel flow the conductances are additive., while in series flow the resistances are additive. Likewise, in order to de- ` tennine the total resistance for the wall, the conductance must be known. The importance of this analysis cannot be over emphasized. This is especially true in wall constructions m which there are parallel paths of ' heat flow and one path has a high heat transfer while others have a low heat transfer. The method of making this calculation can best be shown by the folt?-- a A = this wall was tested bv the hot box methott-'