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American Society of Heating and Ventilating Engineers Guide, 1929 Table 12-B. Coefficients of Transit
Note.--The figures on this page are the combined coefficients of transmission of pitched roofs, uni difference in temperature between the air underneath the ceiling and the outside air. An average accurate for roofs ranging from X pitch to pitch.
,.
Chapter I--Heat Losses from Buildings
of Various Types of Pitched Roofs , and top floor ceilings, and are expressed in B.t.u. per hour pet square foot of roof area per 1 deg. fahr. ' ' --us has been assumed. These coefficients are based on X pitched roofs, but are sufficiently
UkJUtATED
of \SThe values
in this Table are based on the /b(lovmK) Internal
Conductivities CO which are expressed r " L - "
Asphalt or Composition tLoofina
Asbestos Smnqles Slate Stimqles Wood (Yellow Pine or Pir) Wood lath 4 Plaster Plaster Board Plaster (Gypsum)
Tiber insulation (boardfora)
Felt or Quilt Insulation (`icfl) Cart board
Cellular Gypsum (lb*) Flaked Gypsum, Oy (26>s)
fc.50 b. 00 10.37
1.00
2.00 3.04 2.32 0.33 0.27 0.30 0.5<5 a 52
as applied.
0.9 applied.
per. r per 1'
as applied per l` per 1` per r
per r per r
per r
per r
II1 1
L. 4s
-9
3
12
1111 Oood
Type of CeYfmq
1 251 Wood Lath f Plaster (IS)
1 252 Wood Lath t, Plaster (J/z)
I 253 Wood Lath , Plaster ('/z')
1 254 Wood Lath 4 Plaster '('/z) 1 155 Wood Lath $ Plaster Qlz) 1 256 ^Piaster Board 4 Plaster ('A')
Insulation on underside of
i-oof Ea/ters
Insulation between Cetlmq Joists
t
kJone tloae ''fj. fiber Insulation (Board form) Done KJone Done
Done
J
1" felt or Quilt t insulation (So/t)
fiber Insulation t (Board /arm)
3% Cellular. Gypsum Fill
3s/& Flaked
f\U
Uone
257 Cork, board 4 Plaster ('/z)
1 258 t Cork board 4 Plaster i'll)
1 Z5S I Z60
Yl fiber Insulation (board /orm) 4 Plaster (Vz")
'/k (Board
forImns) u4latPiolansterQ/z)
kJone
K)or?e
kJorie
KJone
done.
Q.one
% fiber (nsulatiort (board form.)
)k fiber Insulation (board /orm)
i,&vaasnead wonuaccatupaplutehuicku>neusnsdeorfs1idien.oflucmeiblienrgojof iasptspwroixthimfautrerliyng%stirnip.s between insulation and ceiling, Note.--The coefficient used for plasterboard is 3.04 per inch thickness--recent data indicate values as low i 1.30 for this material. Note.--The coefficient used for cellular gypsum, 0.59 is for 18 lb. weight--weights as low as 12 lb. may be used.
44
tCBaansleadlsoonb1eina.pbplyie4ditno.,usnpdaecresdid2eionf. ceiling joists with fumng strips between insulation and ceiling.
NIBoates.e--dTohneacctoueaflfitchieicnktneussesdoffo1rinp.lalusmtebrbeoraorfdaipsp3ro.0x4impaetreilync%h tihni.ckness--recent data indicate values asAow
s 1.30 for this material.
y
- fr srvnsum. 0.59 is for 18 lb. weight--weights as low as 12 lb. may be used.