WAC 51-11C-610211:

51-11C-61021 << 51-11C-610211 >> 51-11C-61022

Table A102.1

Default U-factors for Ceilings

				Standard Frame	Advanced Frame
Ceilings Below Vented Attics
Flat				Baffled
	R-19			0.049	0.047
	R-30			0.036	0.032
	R-38			0.031	0.026
	R-49			0.027	0.020
	R-60			0.025	0.017
Scissors Truss
	R-30 (4/12 roof pitch)			0.043	0.031
	R-38 (4/12 roof pitch)			0.040	0.025
	R-49 (4/12 roof pitch)			0.038	0.020
	R-30 (5/12 roof pitch)			0.039	0.032
	R-38 (5/12 roof pitch)			0.035	0.026
	R-49 (5/12 roof pitch)			0.032	0.020
Vaulted Ceilings				16" O.C.	24" O.C.
	Vented
	R-19 2x10 joist			0.049	0.048
	R-30 2x12 joist			0.034	0.033
	R-38 2x14 joist			0.027	0.027
	Unvented
	R-30 2x10 joist			0.034	0.033
	R-38 2x12 joist			0.029	0.027
	R-21 + R-21 2x12 joist			0.026	0.025
Roof Deck				4 x Beams, 48" O.C.
R-12.5		2"	Rigid insulation	0.064
R-21.9		3.5"	Rigid insulation	0.040
R-37.5		6"	Rigid insulation	0.025
R-50		8"	Rigid insulation	0.019

[Statutory Authority: RCW 19.27A.020, 19.27A.025 and chapters 19.27 and 34.05 RCW. WSR 13-04-056, § 51-11C-610211, filed 2/1/13, effective 7/1/13.]