APPENDIX 13-B

SUPPLEMENTAL INFORMATION FOR SUB-CHAPTER 4

1.0	General Requirements

1.1 Testing Procedures.

1.1.1 Building Material Thermal Properties. If building material R-values or thermal conductivities are determined by testing, one of the following test procedures shall be used:
a. ASTM C177,
b. ASTM C236,
c. ASTM C518, or
d. ASTM C976.
For concrete, the oven-dried conductivity shall be multiplied by 1.2 to reflect the moisture content as typically installed.

1.1.2 Assembly U-Factors. If assembly U-factors are determined by testing, one of the following test procedures shall be used: 
a. ASTM C236 or
b. ASTM C976.
Product samples tested shall be production line material or representative of material as purchased by the consumer or contractor. If the assembly is too large to be tested at one time in its entirety, then either a representative portion shall be tested or different portions shall be tested separately and a weighted average determined. To be representative, the portion tested shall include edges of panels, joints with other panels, typical framing percentages, and thermal bridges.

1.1.3 Fenestrations and Doors. Product samples used for determining fenestration performance shall be production line units or representative of units as purchased by the consumer or contractor. 

1.2 Calculation Procedures and Assumptions. The following procedures and assumptions shall be used for all calculations. R-values for air films, insulation, and building materials shall be taken from B1.2.1 through B1.2.3, respectively. In addition, the appropriate assumptions listed in B2.1 through B2.5, including framing factors, shall be used.

1.2.1 Air Films: Prescribed R-values for air films shall be as follows:
R-Value 	Condition
0.17		All exterior surfaces
0.46 		All semi-exterior surfaces
0.61		Interior horizontal surfaces, heat flow up
0.92		Interior horizontal surfaces, heat flow down
0.68		Interior vertical surfaces

Exterior surfaces are areas exposed to the wind. Semi-exterior surfaces are protected surfaces that face attics, crawl spaces, and parking garages with natural or mechanical ventilation. Interior surfaces are surfaces within enclosed spaces.  

The R-value for cavity airspaces shall be taken from Table B-1 based on the emissivity of the cavity from Table B-2. No credit shall be given for airspaces in cavities that contain any insulation or less than 0.5 in. The values for 3.5 in. cavities shall be used for cavities of that width and greater.

1.2.2 Insulation R-values: Insulation R-values shall be determined as follows:
a. For insulation that is not compressed, the rated R-value of insulation shall be used.
b. For calculation purposes, the effective R-value for insulation that is uniformly compressed in confined cavities shall be taken from Table B-3.
c. For calculation purposes, the effective R-value for insulation installed in cavities in attic roofs with steel joists shall be taken from Table B-18.
d. For calculation purposes, the effective R-value for insulation installed in cavities in steel-framed walls shall be taken from Table B-17.

1.2.3 Building Material Thermal Properties: R-values for building materials shall be taken from Table B-4. Concrete block R-values shall be calculated using the isothermal planes method or a two-dimensional calculation program, thermal conductivities from Table B-5 and dimensions from ASTM C90. The parallel path calculation method is not acceptable.
Exception: R-values for building materials or thermal conductivities determined from testing in accordance with B1.1

1.2.4 Building Material Heat Capacities: The heat capacity of assemblies shall be calculated using published values for the unit weight and specific heat of all building material components that make up the assembly.

1.3 Insulation Installation. Insulation materials shall be installed in accordance with the insulation installation standards listed in table 6C-2 of Appendix C and in such a manner as to achieve rated R-value of insulation. Open-blown or poured loose-fill insulation shall not be used in attic roof spaces when the slope of the ceiling is more than three in twelve. When eave vents are installed, baffling of the vent openings shall be provided to deflect the incoming air above the surface of the insulation.
Exception: Where metal building roof and metal building wall insulation is compressed between the roof or wall skin and the structure.

1.3.1 Substantial Contact. Insulation shall be installed in a permanent manner in substantial contact with the inside surface in accordance with manufacturer’s recommendations for the framing system used. Flexible batt insulation installed in floor cavities shall be supported in a permanent manner by supports no greater than 24 in. on center.
Exception: Insulation materials that rely on airspaces adjacent to reflective surfaces for their rated performance.

1.3.2 Recessed Equipment. Lighting fixtures; heating, ventilating, and air-conditioning equipment, including wall heaters, ducts, and plenums; and other equipment shall not be recessed in such a manner as to affect the insulation thickness unless:
1.. the total combined area affected (including necessary clearances) is less than one percent of the opaque area of the assembly, or
2. the entire roof, wall, or floor is covered with insulation to the full depth required, or
3. the effects of reduced insulation are included in calculations using an area-weighted average method and compressed insulation values obtained from Table B-3.
In all cases, air leakage through or around the recessed equipment to the conditioned space shall be limited in accordance with section 406.1.ABC.1.2.

1.3.3 Location of Roof Insulation. The roof insulation shall not be installed on a suspended ceiling with removable ceiling panels.

1.3.4 Insulation Protection. Exterior insulation shall be covered with a protective material to prevent damage from sunlight, moisture, landscaping operations, equipment maintenance, and wind. In attics and mechanical rooms, a way to access equipment that prevents damaging or compressing the insulation shall be provided. Foundation vents shall not interfere with the insulation. Insulation materials in ground contact shall have a water absorption rate no greater than 0.3% when tested in accordance with ASTM C272.

1.4  Assembly U-Factor, C-Factor and F-Factor Determination, General 

1.4.1 Pre-Calculated Assembly U-Factors, C-Factors, F-Factors, or Heat Capacities. The U-factors, C-factors, F-factors, and heat capacities for typical construction assemblies are included in B2.1 through B2.5. These values shall be used for all calculations unless otherwise allowed by B1.4.2. Interpolation between values in a particular table in Appendix B is allowed for rated R-values of insulation, including insulated sheathing. Extrapolation beyond values in a table in Appendix B is not allowed.

1.4.2 Applicant-Determined Assembly U-Factors, CFactors, F-Factors, or Heat Capacities. If the building official determines that the proposed construction assembly is not adequately represented in B2.1 through B2.5, the applicant shall determine appropriate values for the assembly using the assumptions in B1.5. An assembly is deemed to be adequately represented if 
a. the interior structure, hereafter referred to as the base assembly, for the class of construction is the same as described in B2.1 through B2.5 and
b. changes in exterior or interior surface building materials added to the base assembly do not increase or decrease the R-value by more than 2 from that indicated in the descriptions in B2.1 through B2.5.  Insulation, including insulated sheathing, is not considered a building material.

1.5 Determination of Alternate Assembly U-Factors, CFactors, F-Factors, or Heat Capacities.  Where the designer chooses to utilize alternate assembly configurations or uses values other than those found in Appendix B2.0 below, the procedures of this section shall be followed.

1.5.1 General. U-factors for fenestration shall be determined in accordance with B1.1.3 or B2.1 only. U-factors for opaque doors shall be determined in accordance with B1.1.3 or B2.3 only. Component U-factors for other opaque assemblies shall be determined in accordance with B1.5 only if approved by the building official in accordance with B1.4.2. The procedures required for each class of construction are specified in B1.5.2. Testing shall be performed in accordance with B1.1. Calculations shall be performed in accordance with B1.2.

1.5.2 Required Procedures. Two- or three-dimensional finite difference and finite volume computer models shall be an acceptable alternative method to calculating the thermal performance values for all assemblies and constructions listed below. The procedures in this section shall also be permitted to determine all alternative U-factors, F-factors, and C-factors:

1.5.2.1 Above-Grade Walls.
(1) Mass walls: testing or the isothermal planes calculation method or two-dimensional calculation method. The parallel path calculation method is not acceptable.
(2) Metal building walls: testing.
(3) Steel-framed walls: testing or parallel path calculation method using the insulation/framing layer adjustment factors in Table B-17 or the modified zone method.
(4) Wood-framed walls: testing or parallel path calculation method.
(5) Other walls: testing or two-dimensional calculation method.

1.5.2.2 Below-Grade Walls.
(1) Mass walls: testing or the isothermal planes calculation method or two-dimensional calculation method. The parallel path calculation method is not acceptable.
(2) Other walls: testing or two-dimensional calculation method.

1.5.2.3 Roofs.
(1) Roofs with insulation entirely above deck: testing or series calculation method.
(2) Metal building roofs: testing.
(3) Attic roofs, wood joists: testing or parallel path calculation method.
(4) Attic roofs, steel joists: testing or parallel path calculation method using the insulation/framing layer adjustment factors in Table B-18 or modified zone calculation method.
(5) Attic roofs, concrete joists: testing or parallel path calculation method if concrete is solid and uniform or isothermal planes calculation method if concrete has hollow sections.
(6) Other attic roofs and other roofs: testing or two dimensional calculation method.

1.5.2.4 Floors.
(1) Mass floors: testing or parallel path calculation method if concrete is solid and uniform or isothermal planes calculation method if concrete has hollow sections.
(2) Steel joist floors: testing or modified zone calculation method.
(3) Wood joist floors: testing or parallel path calculation method or isothermal planes calculation method.
(4) Other floors: testing or two-dimensional calculation method.
(5) Slab-on-Grade Floors: no testing or calculations allowed.

TABLE B-1
Emittance Values of Various Surfaces and Effective Emittances of Air Spaces

Surface	Average Emittance e	Effective Emittance e eff of Air Space	
		One Surface e; Other, 0.9	Both Surfaces Emittance e	
Aluminum foil,bright	0.05	0.05	0.03	
				
Aluminum foil,with condensate just visible(>0.7gr/ft2)	0.3	0.29	-	
				
Aluminum foil,with condensate clearly visible(>2.9gr/ft2)	0.7	0.65	-	
				
Aluminum sheet	0.12	0.12	0.06	
				
Aluminum coated paper,polished	0.2	0.2	0.11	
				
Steel,galv.,bright	0.25	0.24	0.15	
				
Aluminum paint	0.5	0.47	0.35	
				
Bldg materials: wood, paper, masonry, nonmetallic paints	0.9	0.82	0.82	
				
Regular glass	0.84	0.77	0.72	

TABLE B-2
R-Values for Cavity Air Spaces
Component	Airspace Thickness (in.)	R-Value	
		Effective Emissivity	
		0.03	0.05	0.20	0.50	0.82	
	0.5	2.13	2.04	1.54	1.04	0.77	
							
	0.75	2.33	2.22	1.64	1.09	0.8	
							
	1.5	2.53	2.41	1.75	1.13	0.82	
							
	3.5	2.83	2.66	1.88	1.19	0.85	
							
Wall	0.5	2.54	2.43	1.75	1.13	0.82	
							
	0.75	3.58	3.32	2.18	1.3	0.9	
							
	1.5	3.92	3.62	2.3	1.34	0.93	
							
	3.5	3.67	3.4	2.21	1.31	0.91	
							
Floor	0.5	2.55	1.28	1	0.69	0.53	
							
	0.75	1.44	1.38	1.06	0.73	0.54	
							
	1.5	2.49	2.38	1.76	1.15	0.85	
							
	3.5	3.08	2.9	2.01	1.26	0.9	

TABLE B-3 
Effective R-Values for Fiberglass

Insulation R-Value at Standard Thickness	
Rated R-
Standard

Nominal Lumber Size (in.)	Value
Thickness (in.)	38	30	22	21	19	15	13	11	
		12	9.5	6.5	5.5	6	3.5	3.5	3.5	
	
Actual Depth of Cavity (in.)	Effective Insulation R-Values when Installed in a Confined cavity	
2x12	11.25	37	-	-	-	-	-	-	-	
2x10	9.25	32	30	-	-	-	-	-	-	
2x8	7.25	27	26	22	21	19	-	-	-	
2x6	5.5		21	20	21	18		-	-	
2x4	3.5		-	14	-	13	15	13	11	
	2.5		-	-	-	-	-	9.8		
	1.5		-	-	-	-	-	6.3	6	

TABLE B-4 
R-Values for Building Materials
Material	Nominal Size (in.)	Actual Size (in.)	R-Value	
	-	-	1.23	
Concrete at R-0.0625/in.	-	2	0.13	
	-	4	0.25	
	-	6	0.38	
	-	8	0.5	
	-	10	0.63	
	-	12	0.75	
Flooring, wood subfloor	-	0.75	0.94	
Gypsum board	-	0.5	0.45	
	-	0.625	0.56	
Metal deck	-	-	0	
Roofing, built-up	-	0.375	0.33	
Sheathing, vegetable fiber board, 0.78 in.	-	0.78	2.06	
Soil at R-0.104/in.	-	12	1.25	
Steel, mild		1	0.0031807	
Stucco	-	0.75	0.08	
Wood, 2 x 4 at R-1.25/in.	4	3.5	4.38	
Wood, 2 x 6 at R-1.25/in.	6	5.5	6.88	
Wood, 2 x 8 at R-1.25/in.	8	7.25	9.06	
Wood, 2 x 10 at R-1.25/in.	10	9.25	11.56	
Wood, 2 x 12 at R-1.25/in.	12	11.25	14.06	
Wood, 2 x 14 at R-1.25/in.	14	13.25	16.56	

TABLE B-5 
Thermal Conductivity of Concrete Block Material
Concrete Block
Density in lb/ft3	Thermal Conductivity in Btu·in./h·ft2·°F	
80	3.7	
		
85	4.2	
		
90	4.7	
		
95	5.1	
		
100	5.5	
		
105	6.1	
		
110	6.7	
		
115	7.2	
		
120	7.8	
		
125	8.9	
		
130	10	
		
135	11.8	
		
140	13.5	

2.0 Building Envelope Characteristics

2.1 Fenestration. All fenestration with U-factors, SHGC, or visible light transmittance determined, certified, and labeled in accordance with NFRC 100, 200, and 300, respectively, as specified in B1.1.3 shall be assigned those values.

2.1.1 Unlabeled Skylights. Unlabeled skylights shall be assigned the U-factors in Table B-6 and are allowed to use the SHGCs and visible light transmittances in Table B-7. The metal with thermal break frame category shall not be used unless all frame members have a thermal break equal to or greater than 1/4 in.

2.1.2 Unlabeled Vertical Fenestration. Unlabeled vertical fenestration, both operable and fixed, shall be assigned the Ufactors, SHGCs, and visible light transmittances in Table B-8. No credit shall be given for any other features, including metal frames with thermal breaks, low-emissivity coatings, gas fillings, or insulating spacers, other than as determined in accordance with B1.1.3.

TABLE B-6]
Assembly U-Factors for Unlabeled Skylights
Product Type	Sloped Installation	
	Unlabeled Skylight with Curb
(Includes blass/plastic, flat/domed, fixed/operable)	Unlabeled Skylight without Curb
(Includes glass/plastic, flat/domed, fixed/operable)	
Frame Type	Aluminum without Thermal Break	Aluminum with Thermal Break	Reinforced Vinyl/ Aluminum Clad Wood	Wood/ Vinyl	Aluminum without Thermal Break	Aluminum with Thermal Break	Structural Glazing	
ID	Glazing Type								
	Single Glazing								
1	1/8" glass	1.98	1.89	1.75	1.47	1.36	1.25	1.25	
2	1/4" acrylic/polycarb	1.82	1.73	1.6	1.31	1.21	1.1	1.1	
3	1/8" acrylic/polycarb	1.9	1.81	1.68	1.39	1.29	1.18	1.18	
	Double Glazing								
4	1/4" airspace	1.31	1.11	1.05	0.84	0.82	0.7	0.66	
5	1/2" airspace	1.3	1.1	1.04	0.84	0.81	0.69	0.65	
6	1/4" argon space	1.27	1.07	1	0.8	0.77	0.66	0.62	
7	1/2" argon space	1.27	1.07	1	0.8	0.77	0.66	0.62	
	Double Glazing, e=0.60 on	surface 2 or 3							
8	1/4" airspace	1.27	1.08	1.01	0.81	0.78	0.67	0.63	
9	1/2" airspace	1.27	1.07	1	0.8	0.77	0.66	0.62	
10	1/4" argon space	1.23	1.03	0.97	0.76	0.74	0.63	0.58	
11	1/2" argon space	1.23	1.03	0.97	0.76	0.74	0.63	0.58	
	Double Glazing, e=0.40 on	surface 2 or 3							
12	1/4" airspace	1.25	1.05	0.99	0.78	0.76	0.64	0.6	
13	1/2" airspace	1.24	1.04	0.98	0.77	0.75	0.64	0.59	
14	1/4" argon space	1.18	0.99	0.92	0.72	0.7	0.58	0.54	
15	1/2" argon space	1.2	1	0.94	0.74	0.71	0.6	0.56	
	Double Glazing, e=0.20 on	surface 2 or 3							
16	1/4" airspace	1.2	1	0.94	0.74	0.71	0.6	0.56	
17	1/2" airspace	1.2	1	0.94	0.74	0.71	0.6	0.56	
18	1/4" argon space	1.14	0.94	0.88	0.68	0.65	0.54	0.5	
19	1/2" argon space	1.15	0.95	0.89	0.68	0.66	0.55	0.51	
	Double Glazing, e=0.10 on	surface 2 or 3							
20	1/4" airspace	1.18	0.99	0.92	0.72	0.7	0.58	0.54	
21	1/2" airspace	1.18	0.99	0.92	0.72	0.7	0.58	0.54	
22	1/4" argon space	1.11	0.91	0.85	0.65	0.63	0.52	0.47	
23	1/2" argon space	1.13	0.93	0.87	0.67	0.65	0.53	0.49	
	Double Glazing, e=0.05 on	surface 2 or 3							
24	1/4" airspace	1.17	0.97	0.91	0.7	0.68	0.57	0.52	
25	1/2" airspace	1.17	0.98	0.91	0.71	0.69	0.58	0.53	
26	1/4" argon space	1.09	0.89	0.83	0.63	0.61	0.5	0.45	
27	1/2" argon space	1.11	0.91	0.85	0.65	0.63	0.52	0.47	
	Triple Glazing								
28	1/4" airspaces	1.12	0.89	0.84	0.64	0.64	0.53	0.48	
29	1/2" airspaces	1.1	0.87	0.81	0.61	0.62	0.51	0.45	
30	1/4" argon spaces	1.09	0.86	0.8	0.6	0.61	0.5	0.44	
31	1/2" argon spaces	1.07	0.84	0.79	0.59	0.59	0.48	0.42	
	Triple Glazing, e=0.20 on surface	2,3,4, or 5							
32	1/4" airspaces	1.08	0.85	0.79	0.59	0.6	0.49	0.43	
33	1/2" airspaces	1.05	0.82	0.77	0.57	0.57	0.46	0.41	
34	1/4" argon spaces	1.02	0.79	0.74	0.54	0.55	0.44	0.38	
35	1/2" argon spaces	1.01	0.78	0.73	0.53	0.54	0.43	0.37	
	Triple Glazing, e=0.20 on	surfaces 2 or	3 and 4 or 5						
36	1/4" airspaces	1.03	0.8	0.75	0.55	0.56	0.45	0.39	
37	1/2" airspaces	1.01	0.78	0.73	0.53	0.54	0.43	0.37	
38	1/4" argon spaces	0.99	0.75	0.7	0.5	0.51	0.4	0.35	
39	1/2" argon spaces	0.97	0.74	0.69	0.49	0.5	0.39	0.33	
	Triple Glazing, e=0.10 on	surfaces 2 or	3 and 4 or 5						
40	1/4" airspaces	1.01	0.78	0.73	0.53	0.54	0.43	0.37	
41	1/2" airspaces	0.99	0.76	0.71	0.51	0.52	0.41	0.36	
42	1/4" argon spaces	0.96	0.73	0.68	0.48	0.49	0.38	0.32	
43	1/2" argon spaces	0.95	0.72	0.67	0.47	0.48	0.37	0.31	
	Quadruple Glazing, e=0.10 on	surfaces 2 or	3 and 4 or 5						
44	1/4" airspaces	0.97	0.74	0.69	0.49	0.5	0.39	0.33	
45	1/2" airspaces	0.94	0.71	0.66	0.46	0.47	0.36	0.3	
46	1/4" argon spaces	0.93	0.7	0.65	0.45	0.46	0.35	0.3	
47	1/2" argon spaces	0.91	0.68	0.63	0.43	0.44	0.33	0.28	
48	1/4" krypton spaces	0.88	0.65	0.6	0.4	0.42	0.31	0.25	

TABLE B-7 
Assembly Solar Heat Gain Coefficients (SHGC) and
Assembly Visible Light Transmittances (VLT) for Unlabeled Skylights

Glass  Type 	Glazing Type:  
Number of glazing layers Number & emissivity of coatings (glazing is glass except where noted

                                                                Frame:

                                                               Characteristic:	Unlabeled Skylights (includes glass/plastic, flat/domed, fixed/operable)	
		Metal without thermal break	Metal with thermal break	Wood/vinyl/ fiberglass	
		SHGC	VLT	SHGC	VLT	SHGC	VLT	
Clear	Single glazing, 1/8 in. glass	0.82	0.76	0.78	0.76	0.73	0.73	
								
	Single glazing, 1/4 in. glass	0.78	0.75	0.74	0.75	0.69	0.72	
								
	Single glazing, acrylic/polycarbonate	0.83	0.92	0.83	0.92	0.83	0.92	
								
	Double glazing	0.68	0.66	0.64	0.66	0.59	0.64	
								
	Double glazing, E=0.40 on surface 2 or 3	0.71	0.65	0.67	0.65	0.62	0.63	
								
	Double glazing, E=0.20 on surface 2 or 3	0.66	0.61	0.62	0.61	0.57	0.59	
								
	Double glazing, E=0.10 on surface 2 or 3	0.59	0.63	0.55	0.63	0.51	0.61	
								
	Double glazing, acrylic/polycarbonate	0.77	0.89	0.77	0.89	0.77	0.89	
								
	Triple glazing	0.6	0.59	0.56	0.59	0.52	0.57	
								
	Triple glazing, E=0.40 on surface 2, 3, 4, or 5	0.64	0.6	0.6	0.6	0.56	0.57	
								
	Triple glazing, E=0.20 on surface 2, 3, 4, or 5	0.59	0.55	0.55	0.55	0.51	0.53	
								
	Triple glazing, E=0.10 on surface 2, 3, 4, or 5	0.54	0.56	0.5	0.56	0.46	0.54	
								
	Triple glazing, E=0.40 on surfaces 3 and 5	0.62	0.57	0.58	0.57	0.53	0.55	
								
	Triple glazing, E=0.20 on surfaces 3 and 5	0.56	0.51	0.52	0.51	0.48	0.49	
								
	Triple glazing, E=0.10 on surfaces 3 and 5	0.47	0.54	0.43	0.54	0.4	0.52	
								
	Triple glazing, acrylic/polycarbonate	0.71	0.85	0.71	0.85	0.71	0.85	
								
	Quadruple glazing, E=0.10 on surfaces 3 and 5	0.41	0.48	0.37	0.48	0.33	0.46	
								
	Quadruple glazing, acrylic/polycarbonate	0.65	0.81	0.65	0.81	0.65	0.81	
								
Tinted	Single glazing, 1/8 in. glass	0.7	0.58	0.66	0.58	0.62	0.56	
								
	Single glazing, 1/4 in. glass	0.61	0.45	0.56	0.45	0.52	0.44	
								
	Single glazing, acrylic/polycarbonate	0.46	0.27	0.46	0.27	0.46	0.27	
								
	Double glazing	0.5	0.4	0.46	0.4	0.42	0.39	
								
	Double glazing, E=0.40 on surface 2 or 3	0.59	0.5	0.55	0.5	0.5	0.48	
								
	Double glazing, E=0.20 on surface 2 or 3	0.47	0.37	0.43	0.37	0.39	0.36	
								
	Double glazing, E=0.10 on surface 2 or 3	0.43	0.38	0.39	0.38	0.35	0.37	
								
	Double glazing, acrylic/polycarbonate	0.37	0.25	0.37	0.25	0.37	0.25	
								
	Triple glazing	0.42	0.22	0.37	0.22	0.34	0.21	
								
	Triple glazing, E=0.40 on surface 2, 3, 4, or 5	0.53	0.45	0.49	0.45	0.45	0.44	
								
	Triple glazing, E=0.20 on surface 2, 3, 4, or 5	0.42	0.33	0.38	0.33	0.35	0.32	
								
	Triple glazing, E=0.10 on surface 2, 3, 4, or 5	0.39	0.34	0.35	0.34	0.31	0.33	
								
	Triple glazing, E=0.40 on surfaces 3 and 5	0.51	0.43	0.47	0.43	0.43	0.42	
								
	Triple glazing, E=0.20 on surfaces 3 and 5	0.4	0.31	0.36	0.31	0.32	0.29	
								
	Triple glazing, E=0.10 on surfaces 3 and 5	0.34	0.32	0.3	0.32	0.27	0.31	
								
	Triple glazing, acrylic/polycarbonate	0.3	0.23	0.3	0.23	0.3	0.23	
								
	Quadruple glazing, E=0.10 on surfaces 3 and 5	0.3	0.29	0.26	0.29	0.23	0.28	
								
	Quadruple glazing, acrylic/polycarbonate	0.27	0.25	0.27	0.25	0.27	0.25	

TABLE B-8 
Assembly U-Factors, Assembly Solar Heat Gain Coefficients (SHGC), and Assembly Visible Light
Transmittances (VLT) for Unlabeled Vertical Fenestration
	Unlabeled Vertical Fenestration	
All frame types

                                                  Singleglazing

                                                  Glassblock	Clear Glass	Tinted Glass	
	U-Factor	SHGC	VLT	U-Factor	SHGC	VLT	
	1.25	0.82	0.76	1.25	0.7	0.58	
							
	0.6	0.56	0.56	n.a.	n.a.	n.a.	
Wood, vinyl, or fiberglass frame

                                                  Doubleglazing

                                                  Tripleglazing							
							
	0.6	0.59	0.64	0.6	0.42	0.39	
							
	0.45	0.52	0.57	0.45	0.34	0.21	
Metal and other frame types

                                                  Doubleglazing

                                                  Tripleglazing							
							
	0.9	0.68	0.66	0.9	0.5	0.4	
							
	0.7	0.6	0.59	0.7	0.42	0.22	

2.2  Walls
2.2.1 Above-Grade Walls

2.2.1.1 Mass Wall. U-factors for mass walls shall be taken from Table B-9 or determined by the procedure in this subsection. It is acceptable to use the U-factors in Table B-9 for all mass walls, provided that the grouting is equal to or less than that specified. Heat capacity for mass walls shall be taken from Table B-10 or B-11.
Exception: U-factors for mass walls determined in accordance with section 402.1.C.1. 
For the purpose of B1.4.2, the base assembly is a masonry or concrete wall. Continuous insulation is installed on the interior, exterior, or within the masonry units, or it is installed on the interior or exterior of the concrete. The U-factor includes R-0.17 for exterior air film and R-0.68 for interior air film, vertical surfaces. For insulated walls, the U-factor also includes R-0.45 for 0.5 in. gypsum board. U-factors are provided for the following configurations:
a. Concrete wall: 8 in. normal weight concrete wall with a density of 145 lb/ft3.
b. Solid grouted concrete block wall: 8 in. medium weight ASTM C90 concrete block with a density of 115 lb/ft3 and solid grouted cores.
c. Partially grouted concrete block wall: 8 in. medium weight ASTM C90 concrete block with a density of 115 lb/ft3 having reinforcing steel every 32 in. vertically and every 48 in. horizontally, with cores grouted in those areas only. Other cores are filled with insulating material only if there is no other insulation. If not taken from Table B-9, mass wall U-factors shall be determined from Tables B-10, B-10, and B-12 using the following procedure.
d. If the mass wall is uninsulated or only the cells are insulated:
1. For concrete walls, determine the U-factor from Table B-10 based on the concrete density and wall thickness.
2. For concrete block walls, determine the U-factor from Table B-11 based on the block size, concretendensity, degree of grouting in the cells, and whether the cells are insulated.
e. If the mass wall has additional insulation:
1. For concrete walls, determine the Ru from Table B-10 based on the concrete density and wall thickness. Next, determine the effective R-value for the insulation/ framing layer from Table B-12 based on the rated R-value of insulation installed, the thickness of the insulation, and whether it is installed between wood or metal framing or with no framing. Then, determine the U-factor by adding the Ru and the effective R-value together and taking the inverse of the total.
2. For concrete block walls, determine the Ru from Table B-11 based on the block size, concrete density, degree of grouting in the cells, and whether the cells are insulated. Next, determine the effective R-value for the insulation/framing layer from Table B-12 based on the rated R-value of insulation installed, the thickness of the insulation, and whether it is installed between wood or metal framing or with no framing. Then, determine the U-factor by adding the Ru and the effective R-value together and taking the inverse of the total.

2.2.1.2 Metal Building Walls. U-factors for metal building walls shall be taken from Table B-13. It is not acceptable to use these U-factors if additional insulation is not continuous. For the purpose of B1.4.2, the base assembly is a wall where the insulation is compressed between metal wall panels and the metal structure. Additional assemblies include continuous insulation, uncompressed and uninterrupted by framing.

2.2.1.3 Steel-Framed Walls. U-factors for steel-framed walls shall be taken from Table B-14. For steel-framed walls with framing at less than 24 in. on center, use the standard framing values as described in (a) below. For steel-framed walls with framing from 24 in. to 32 in. on center, use the advanced framing values as described in (b) below. For steel-framed walls with framing greater than 32 in. on center, use the metal building wall values in Table B-13. For the purpose of B1.4.2, the base assembly is a wall where the insulation is installed within the cavity of the steel stud framing but where there is not a metal exterior surface spanning member. The steel stud framing is a minimum uncoated thickness of 0.043 in. for 18 gauge or 0.054 in. for 16 gauge. The U-factor includes R-0.17 for exterior air film, R-0.08 for stucco, R-0.56 for 0.625 in.16 mm gypsum board on the exterior, R-0.56 for 0.625 in.16 mm gypsum board on the interior, and R-0.68 for interior vertical surfaces air film. The performance of the insulation/framing layer is calculated using the values in Table B-17. Additional assemblies include continuous insulation, uncompressed and uninterrupted by framing. U-factors are provided for the following configurations:
a. Standard framing: steel stud framing at 16 in. on center with cavities filled with 16 in. wide insulation for both 3.5 in. deep and 6.0 in. deep wall cavities.
b. Advanced framing: steel stud framing at 24 in. on center with cavities filled with 24 in. wide insulation for both 3.5 in. deep and 6.0 in. deep wall cavities.

2.2.1.4 Wood-Framed Walls. U-factors for wood-framed walls shall be taken from Table B-15. For wood-framed walls with framing at less than 24 in. on center, use the standard framing values as described in (a) below. For wood-framed walls with framing from 24 in. to 32 in. on center, use the advanced framing values as described in (b) below if the headers are uninsulated or the advanced framing with insulated headers values as described in (c) below if the headers are insulated. For wood-framed walls with framing greater than 32 in. on center, U-factors shall be determined in accordance with B1.5. For the purpose of B1.4.2, the base assembly is a wall where the insulation is installed between 2 in. nominal wood framing. Cavity insulation is full depth, but values are taken from Table B-3 for R-19 insulation, which is compressed when installed in a 5.5 in. cavity. Headers are double 2 in. nominal wood framing. The U-factor includes R-0.17 for exterior air film, R-0.08 for stucco, R-0.56 for 0.625 in. gypsum board on the exterior, R-0.56 for 0.625 in. gypsum board on the interior, and R-0.68 for interior air film, vertical surfaces. Additional assemblies include continuous insulation, uncompressed and uninterrupted by framing. U-factors are provided for the following configurations: 
a. Standard framing: wood framing at 16 in. on center with cavities filled with 14.5 in. wide insulation for both 3.5 in. deep and 5.5 in. deep wall cavities. Double headers leave no cavity. Weighting factors are 75% insulated cavity, 21% studs, plates, and sills, and 4% headers.
b. Advanced framing: wood framing at 24 in. on center with cavities filled with 22.5 in. wide insulation for both 3.5 in. deep and 5.5 in. deep wall cavities. Double headers leave uninsulated cavities. Weighting factors are 78% insulated cavity, 18% studs, plates, and sills, and 4% headers.
c. Advanced framing with insulated headers: wood framing at 24 in. on center with cavities filled with 22.5 in. wide insulation for both 3.5 in. deep and 5.5 in. deep wall cavities. Double header cavities are insulated. Weighting factors are 78% insulated cavity, 18% studs, plates, and sills, and 4% headers.

2.2.2 Below-Grade Walls. C-factors for below-grade walls shall be taken from Table B-16 or determined by the procedure described in this subsection. It is acceptable to use the C-factors in Table B-16 for all below-grade walls. The base assembly is 8 in. medium-weight concrete block with a density of 115 lb/ft3 and solid grouted cores. Continuous insulation is installed on the interior or exterior. In contrast to the U-factor for above-grade walls, the C-factor for below grade walls does not include R-values for exterior or interior air films or for soil. For insulated walls, the C-factor does include R-0.45 for 0.5 in. gypsum board. If not taken from Table B-16, below-grade wall C-factors shall be determined from Tables B-10, B-11, and B-12 using the following procedure:
a. If the below-grade wall is uninsulated or only the cells are insulated:
(1) For concrete walls, determine the C-factor from Table B-10 based on the concrete density and wall thickness.
(2) For concrete block walls, determine the C-factor from Table B-11 based on the block size, concrete density, degree of grouting in the cells, and whether the cells are insulated.
b. If the mass wall has additional insulation:  
(1) For concrete walls, determine the Rc from Table B-10 based on the concrete density and wall thickness. Next, determine the effective R-value for the insulation/framing layer from Table B-12 based on the rated R-value of insulation installed, the thickness of the insulation, and whether it is installed between wood or metal framing or with no framing. Then, determine the C-factor by adding the Rc and the effective R-value together and taking the inverse of the total. 
(2) For concrete block walls, determine the Rc from Table B-10 based on the block size, concrete density, degree of grouting in the cells, and whether the cells are insulated. Next, determine the effective R-value for the insulation/ framing layer from Table B-11 based on the rated R-value of insulation installed, the thickness of the insulation, and whether it is installed between wood or metal framing or with no framing. Then, determine the C-factor by adding the Rc and the effective R-value together and taking the inverse of the total.

TABLE B-9
Assembly U-Factors for Above-Grade Concrete Walls and Masonry Walls
Framing Type
and Depth	Rated R-Value of
Insulation Alone	Assembly U-Factors for
8 in. Normal
Weight 145 lb/ft3
Solid Concrete Walls	Assembly U-Factors for 8 in.
Medium Weight 115 lb/ft3
Concrete Block Walls:
Solid Grouted	Assembly U-Factors for 8 in.
Medium Weight 115 lb/ft3
Concrete Block Walls:
Partially Grouted (cores uninsulated
except where specified)	
No Framing	R-0	U-0.740	U-0.580	U-0.480	
	Ungrouted Cores
Filled with
Loose-fill insulation	N.A.	N.A.	U-0.350	
Continuous metal framing at 24 in. on center horizontally	
3.5 in.
3.5 in.
3.5 in.	R-11.0
R-13.0
R-15.0	U-0.168
U-0.161
U-0.155	U-0.158
U-0.152
U-0.147	U-0.149
U-0.144
U-0.140	
4.5 in.
4.5 in.
4.5 in.	R-17.1
R-22.5
R-25.2	U-0.133
U-0.124
U-0.122	U-0.126
U-0.119
U-0.116	U-0.121
U-0.114
U-0.112	
5.0 in.
5.0 in.
5.0 in.
5.5 in.
5.5 in.
5.5 in.
5.5 in.
5.5 in.	R-19.0
R-25.0
R-28.0
R-19.0
R-20.9
R-21.0
R-27.5
R-30.8	U-0.122
U-0.115
U-0.112
U-0.118
U-0.114
U-0.113
U-0.106
U-0.104	U-0.117
U-0.110
U-0.107
U-0.113
U-0.109
U-0.109
U-0.102
U-0.100	U-0.112
U-0.106
U-0.103
U-0.109
U-0.105
U-0.105
U-0.099
U-0.096	
6.0 in.
6.0 in.
6.0 in.	R-22.8
R-30.0
R-33.6	U-0.106
U-0.099
U-0.096	U-0.102
U-0.095
U-0.093	U-0.098
U-0.092
U-0.090	
6.5 in.	R-24.7	U-0.099	U-0.096	U-0.092	
7.0 in.	R-26.6	U-0.093	U-0.090	U-0.087	
7.5 in.	R-28.5	U-0.088	U-0.085	U-0.083	
8.0 in.	R-30.4	U-0.083	U-0.081	U-0.079	
1 in. metal clips at 24 in. on center horizontally and 16 in. vertically	
1.0 in.
1.0 in.
1.0 in.	R-3.8
R-5.0
R-5.6	U-0.210
U-0.184
U-0.174	U-0.195
U-0.172
U-0.163	U-0.182
U-0.162
U-0.154	
1.5 in.
1.5 in.
1.5 in.	R-5.7
R-7.5
R-8.4	U-0.160
U-0.138
U-0.129	U-0.151
U-0.131
U-0.123	U-0.143
U-0.125
U-0.118	
2.0 in.
2.0 in.
2.0 in.	R-7.
R-10.0
R-11.2	U-0.129
U-0.110
U-0.103	U-0.123
U-0.106
U-0.099	U-0.118
U-0.102
U-0.096	
2.5 in.
2.5 in.
2.5 in.	R-9.
R-12.
R-14.0	U-0.109
U-0.092
U-0.086	U-0.104
U-0.089
U-0.083	U-0.101
U-0.086
U-0.080	
3.0 in.
3.0 in.
3.0 in.	R-11.4
R-15.0
R-16.8	U-0.094
U-0.078
U-0.073	U-0.090
U-0.076
U-0.071	U-0.088
U-0.074
U-0.069	
3.5 in.
3.5 in
3.5 in.	R-13.3
R-17.5
R-19.6	U-0.082
U-0.069
U-0.064	U-0.080
U-0.067
U-0.062	U-0.077
U-0.065
U-0.061	

TABLE B-9.   Assembly U-Factors for Above-Grade Concrete Walls and Masonry Walls, 
Framing Type
and Depth	Rated R-Value of
Insulation Alone	Assembly U-Factors for
8 in. Normal
Weight 145 lb/ft3
Solid Concrete Walls	Assembly U-Factors for 8 in.,Medium Weight 115 lb/ft3 Concrete Block Walls:
Solid Grouted	Assembly U-Factors for 8 in.
Medium Weight 115 lb/ft3
Concrete Block Walls: Partially Grouted (cores uninsulated except where specified)	
No Framing	R-0	U-0.740	U-0.580	U-0.480	
	Ungrouted Cores Filled with Loose-fill insulation	
N.A.	
N.A.	
U-0.350	
1 in. metal clips at 24 in. on center horizontally and 16 in. vertically	
4.0 in
4.0 in.
4.0 in.	R-15.2
R-20.0
R-22.4	U-0.073
U-0.061
U-0.057	U-0.071
U-0.060
U-0.056	U-0.070
U-0.058
U-0.054	
5.0 in
6.0 in.
7.0 in.
8.0 in.
9.0 in.
10.0 in.
11.0 in.	. R-28.0
R-33.6
R-39.2
R-44.8
R-50.4
R-56.0
R-61.6	U-0.046
U-0.039
U-0.034
U-0.030
U-0.027
U-0.024
U-0.022	U-0.046
U-0.039
U-0.034
U-0.030
U-0.027
U-0.024
U-0.022	U-0.045
U-0.038
U-0.033
U-0.029
U-0.026
U-0.024
U-0.022	
Continuous insulation uninterrupted by framing	
No Framing
No Framing
No Framing
No Framing
No Framing	R-1.0
R-2.0
R-3.0
R-4.0
R-5.0	U-0.425
U-0.298
U-0.230
U-0.187
U-0.157	U
U
U
U
U	U-0.324
U-0.245
U-0.197
U-0.164
U-0.141	
No Framing
No Framing
No Framing
No Framing
No Framing	R-6.0
R-7.0
R-8.0
R-9.0
R-10.0	U-0.
U-0.120
U-0.107
U-0.097
U-0.088	U-0.129
U-0.115
U-0.103
U-0.093
U-0.085	U-0.124
U-0.110
U-0.099
U-0.090
U-0.083	
No Framing
No Framing
No Framing
No Framing
No Framing	R-11.0
R-12.0
R-13.0
R-14.0
R-15.0	U-0.081 U
U-0.075
U-0.070
U-0.065
U-0.061	U-0.079
U-0.073
U-0.068
U-0.064
U-0.060	U-0.076
U-0.071
U-0.066
U-0.062
U-0.059	
No Framing
No Framing
No Framing
No Framing
No Framing	R-16.0
R-17.0
R-18.0
R-19.0
R-20.0	U-0.
U-0.054
U-0.052
U-0.049
U-0.047	U-0.056
U-0.053
U-0.051
U-0.048
U-0.046	U-0.055
U-0.052
U-0.050
U-0.047
U-0.045	
No Framing
No Framing
No Framing
No Framing
No Framing	R-21.0
R-22.0
R-23.0
R-24.0
R-25.0	U-0.045
U-0.043
U-0.041
U-0.039
U-0.038	U-0.044
U-0.042
U-0.040
U-0.039
U-0.037	U-0.043
U-0.042
U-0.040
U-0.038
U-0.037	
No Framing
No Framing
No Framing
No Framing
No Framing
No Framing
No Framing	R-30.0
R-35.0
R-40.0
R-45.0
R-50.0
R-55.0
R-60.0	U-0.032
U-0.028
U-0.024
U-0.022
U-0.019
U-0.018
U-0.016	U-0.032
U-0.027
U-0.024
U-0.021
U-0.019
U-0.018
U-0.016	U-0.031
U-0.027
U-0.024
U-0.021
U-0.019
U-0.018
U-0.016	

TABLE B-10 
Assembly U-Factors, C-Factors, Ru, Rc, and Heat Capacity for Concrete
Density in lb/ft3	Properties	Thickness in Inches
     3               4             5            6             7            8             9             10          11            12	
20	U-factor	0.22	0.17	0.14	0.12	0.10	0.09	0.08 	0.07	0.07	0.06	
	C-factor	0.27	0.20	0.16	0.13	0.11	0.10	0.09	0.08	0.07	0.07	
	Ru	4.60	5.85	7.10	8.35	9.60	10.85	12.10	13.35	14.60	15.85	
	Rc	3.75	5.00	6.25	7.50	8.75	10.00	11.25	12.50	13.75	15.00	
	HC	1.0	1.3	1.7	2.0	2.3	2.7	3.0	3.3	3.7	4.0	
30	U-factor	0.28	0.22	0.19	0.16	0.14	0.12	0.11	0.10	0.09	0.09	
	C-factor	0.37	0.28	0.22	0.18	0.16	0.14	0.12	0.11	0.10	0.09	
	Ru	3.58	4.49	5.40	6.30	7.21	8.12	9.03	9.94	10.85	11.76	
	Rc	2.73	3.64	4.55	5.45	6.36	7.27	8.18	9.09	10.00	10.91	
	HC	1.5	2.0	2.5	3.0	3.5	4.0	4.5	5.0	5.5	6.0	
40	U-factor	0.33	0.27	0.23	0.19	0.17	0.15	0.14	0.13	0.11	0.11	
	C-factor	0.47	0.35	0.28	0.23	0.20	0.18	0.16	0.14	0.13	0.12	
	Ru	2.99	3.71	4.42	5.14	5.85	6.56	7.28	7.99	8.71	9.42	
	Rc	2.14	2.86	3.57	4.29	5.00	5.71	6.43	7.14	7.86	8.57	
	HC	2.0	2.7	3.3	4.0	4.7	5.3	6.0	6.7	7.3	8.0	
50	U-factor	0.38	0.31	0.26	0.23	0.20	0.18	0.16	0.15	0.14	0.13	
	C-factor	0.57	0.43	0.34	0.28	0.24	0.21	0.19	0.17	0.15	0.14	
	Ru	2.61	3.2	3.79	4.38	4.97	5.56	6.14	6.73	7.32	7.91	
	Rc	1.76	2.35	2.94	3.53	4.12	4.71	5.29	5.88	6.47	7.06	
	HC	2.5	3.3	4.2	5.0	5.8	6.7	7.5	8.3	9.2	10.0	
85	U-factor	0.65	0.56	0.50	0.44	0.40	0.37	0.34	0.31	0.29	0.27	
	C-factor	1.43	1.08	0.86	0.71	0.61	0.54	0.48	0.43	0.39	0.36	
	Ru	1.55	1.78	2.01	2.25	2.48	2.71	2.94	3.18	3.41	3.64	
	Rc	0.70	0.93	1.16	1.40	1.63	1.86	2.09	2.33	2.56	2.79	
	HC	4.3	5.7	7.1	8.5	9.9	11.3	12.8	14.2	15.6	17.0	
95	U-factor	0.72	0.64	0.57	0.52	0.48	0.44	0.41	0.38	0.36	0.33	
	C-factor	1.85	1.41	1.12	0.93	0.80	0.70	0.62	0.56	0.51	0.47	
	Ru	1.39	1.56	1.74	1.92	2.10	2.28	2.46	2.64	2.81	2.99	
	Rc	0.54	0.71	0.89	1.07	1.25	1.43	1.61	1.79	1.96	2.14	
	HC	4.8	6.3	7.9	9.5	11.1	12.7	14.3	15.8	17.4	19.0	
105	U-factor	0.79	0.71	0.65	0.59	0.54	0.51	0.47	0.44	0.42	0.39	
	C-factor	2.38	1.79	1.43	1.18	1.01	0.88	0.79	0.71	0.65	0.59	
	Ru	1.27	1.41	1.557	1.70	1.84	1.98	2.12	2.26	2.40	2.54	
	Rc	0.42	0.56	0.70	0.85	0.99	1.13	1.27	1.41	1.55	1.69	
	HC	5.3	7.0	8.8	10.5	12.3	14.0	15.8	17.5	19.3	21.0	
115	U-factor	0.84	0.77	0.70	0.65	0.61	0.57	0.53	0.50	0.48	0.45	
	C-factor	2.94	2.22	1.75	1.47	1.25	1.10	0.98	0.88	0.80	0.74	
	Ru	1.19	1.30	1.42	1.53	1.65	1.76	1.87	1.99	2.10	2.21	
	Rc	0.34	0.45	0.57	0.68	0.80	0.91	1.02	1.14	1.25	1.36	
	HC	5.8	7.7	9.6	11.5	13.4	15.3	17.3	19.2	21.1	23.0	
125	U-factor	0.88	0.82	0.76	0.71	0.67	0.63	0.60	0.56	0.53	0.51	
	C-factor	3.57	2.70	2.17	1.79	1.54	1.35	1.20	1.08	0.98	0.90	
	Ru	1.13	1.22	1.31	1.41	1.50	1.59	1.68	1.78	1.87	1.96	
	Rc	0.28	0.37	0.46	0.56	0.65	0.74	0.83	0.93	1.02	1.11	
	HC	6.3	8.3	10.4	12.5	14.6	16.7	18.8	20.8	22.9	25.0	
135	U-factor	0.93	0.87	0.82	0.77	0.73	0.69	0.66	0.63	0.60	0.57	
	C-factor	4.55	3.33	2.70	2.22	1.92	1.67	1.49	1.33	1.22	1.11	
	Ru	1.07	1.15	1.22	1.30	1.37	1.45	.52	1.60	1.67	1.75	
	Rc	0.22	0.30	0.37	0.45	0.52	0.60	0.67	0.75	0.82	0.90	
	HC	6.8	9.0	11.3	13.5	15.8	18.0	20.3	22.5	24.8	27.0	
144	U-factor	0.96	0.91	0.86	0.81	0.78	0.74	0.71	0.68	0.65	0.63	
	C-factor	5.26	4.00	3.23	2.63	2.27	2.00	1.79	1.59	1.45	1.33	
	Ru	1.04	1.10	1.16	1.23	1.29	1.35	1.41	1.48	1.54	1.60	
	Rc	0.19	0.25	0.31	0.38	0.44	0.50	0.56	0.63	0.69	0.75	
	HC	7.2	9.6	12.0	14.4	16.8	19.2	21.6	24.0	26.4	28.8	
The U-factors and Ru include standard air film resistances.
The C-factors and Rc are for the same assembly without air film resistances.
Note that the following assemblies do not qualify as a mass wall or mass floor:  3 in. thick concrete with densities of 85, 95, 125 and 135 lbs/ft3  

TABLE B-11 
Assembly U-Factors, C-Factors, Ru, Rc, and Heat Capacity for Concrete Block Walls
Density	Properties	Concrete Block Grouting and Cell Treatment	
		Solid grouted	Partly Grouted, Cells Empty	Partly Grouted, Cells Insulated	Unreinforced, Cells Empty	Unreinforced, Cells Insulated	
6 in. block	
85	U-factor	0.57	0.46	0.34	0.4	0.2	
	C-factor	1.11	0.75	0.47	0.6	0.23	
	Ru	1.75	2.18	2.97	2.52	5.13	
	Rc	0.9	1.33	2.12	1.67	4.28	
	HC	10.9	6.7	7	4.2	4.6	
95	U-factor	0.61	0.49	0.36	0.42	0.22	
	C-factor	1.25	0.83	0.53	0.65	0.27	
	Ru	1.65	2.06	2.75	2.38	4.61	
	Rc	0.8	1.21	1.9	1.53	3.76	
	HC	11.4	7.2	7.5	4.7	5.1	
105	U-factor	0.64	0.51	0.39	0.44	0.24	
	C-factor	1.38	0.91	0.58	0.71	0.3	
	Ru	1.57	1.95	2.56	2.26	4.17	
	Rc	0.72	1.1	1.71	1.41	3.32	
	HC	11.9	7.7	7.9	5.1	5.6	
115	U-factor	0.66	0.54	0.41	0.46	0.26	
	C-factor	1.52	0.98	0.64	0.76	0.34	
	Ru	1.51	1.87	2.41	2.16	3.79	
	Rc	0.66	1.02	1.56	1.31	2.94	
	HC	12.3	8.1	8.4	5.6	6	
125	U-factor	0.7	0.56	0.45	0.49	0.3	
	C-factor	1.7	1.08	0.73	0.84	0.4	
	Ru	1.44	1.78	2.23	2.04	3.38	
	Rc	0.59	0.93	1.38	1.19	2.53	
	HC	12.8	8.6	8.8	6	6.5	
135	U-factor	0.73	0.6	0.49	0.53	0.35	
	C-factor	1.94	1.23	0.85	0.95	0.49	
	Ru	1.36	1.67	2.02	1.9	2.89	
	Rc	0.51	0.82	1.17	1.05	2.04	
	HC	13.2	9	9.3	6.5	6.9	
8 in. block	
85	U-factor	0.49	0.41	0.28	0.37	0.15	
	C-factor	0.85	0.63	0.37	0.53	0.17	
	Ru	2.03	2.43	3.55	2.72	6.62	
	Rc	1.18	1.58	2.7	1.87	5.77	
	HC	15	9	9.4	5.4	6	
95	U-factor	0.53	0.44	0.31	0.39	0.17	
	C-factor	0.95	0.7	0.41	0.58	0.2	
	Ru	1.9	2.29	3.27	2.57	5.92	
	Rc	1.05	1.44	2.42	1.72	5.07	
	HC	15.5	9.6	10	6	6.6	
105	U-factor	0.55	0.46	0.33	0.41	0.19	
	C-factor	1.05	0.76	0.46	0.63	0.22	
	Ru	1.81	2.17	3.04	2.44	5.32	
	Rc	0.96	1.32	2.19	1.59	4.47	
	HC	16.1	10.2	10.6	6.6	7.2	
115	U-factor	0.58	0.48	0.35	0.43	0.21	
	C-factor	1.14	0.82	0.5	0.68	0.25	
	Ru	1.72	2.07	2.84	2.33	4.78	
	Rc	0.87	1.22	1.99	1.48	3.93	
	HC	16.7	10.8	11.2	7.2	7.8	
125	U-factor	0.61	0.51	0.38	0.45	0.24	
	C-factor	1.27	0.9	0.57	0.74	0.3	
	Ru	1.64	1.96	2.62	2.2	4.2	
	Rc	0.79	1.11	1.77	1.35	3.35	
	HC	17.3	11.4	11.8	7.8	8.4	
135	U-factor	0.65	0.55	0.42	0.49	0.28	
	C-factor	1.44	1.02	0.67	0.83	0.37	
	Ru	1.54	1.83	2.35	2.05	3.55	
	Rc	0.69	0.98	1.5	1.2	2.7	
	HC	17.9	12	12.4	8.4	9	

TABLE B-12 
Effective R-Values for Insulation/Framing Layers Added to Above-Grade Mass Walls and Below-Grade Walls
Depth (in.)	Framing Type	Rated R-Value of Insulation	
		0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	
																												
Effective R-value if continuous insulation uninterrupted by framing (includes gypsun board)	
																												
	None	0.5	1.5	2.5	3.5	4.5	5.5	6.5	7.5	8.5	9.5	10.5	11.5	12.5	13.5	14.5	15.5	16.5	17.5	18.5	19.5	20.5	21.5	22.5	23.5	24.5	25.5	
																												
Effective R-value if insulation is installed in cavity between framing (includes gypsum board)		
																												
0.5	Wood	1.3	1.3	1.9	2.4	2.7	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
	Metal	0.9	0.9	1.1	1.1	1.2	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
0.75	Wood	1.4	1.4	2.1	2.7	3.1	3.5	3.8	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
	Metal	1	1	1.3	1.4	1.5	1.5	1.6	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
1	Wood	1.3	1.5	2.2	2.9	3.4	3.9	4.3	4.6	4.9	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
	Metal	1	1.1	1.4	1.6	1.7	1.8	1.8	1.9	1.9	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
1.5	Wood	1.3	1.5	2.4	3.1	3.8	4.4	4.9	5.4	5.8	6.2	6.5	6.8	7.1	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
	Metal	1.1	1.2	1.6	1.9	2.1	2.2	2.3	2.4	2.5	2.5	2.6	2.6	2.7	na	na	na	na	na	na	na	na	na	na	na	na	na	
																												
2	Wood	1.4	1.5	2.5	3.3	4	4.7	5.3	5.9	6.4	6.9	7.3	7.7	8.1	8.4	8.7	9	9.3	na	na	na	na	na	na	na	na	na	
																												
	Metal	1.1	1.2	1.7	2.1	2.3	2.5	2.7	2.8	2.9	3	3.1	3.2	3.2	3.3	3.3	3.4	3.4	na	na	na	na	na	na	na	na	na	
																												
2.5	Wood	1.4	1.5	2.5	3.4	4.2	4.9	5.6	6.3	6.8	7.4	7.9	8.4	8.8	9.2	9.6	10	10.3	10.6	10.9	11.2	11.5	na	na	na	na	na	
																												
	Metal	1.2	1.3	1.8	2.3	2.6	2.8	3	3.2	3.3	3.5	3.6	3.6	3.7	3.8	3.9	3.9	4	4	4.1	4.1	4.1	na	na	na	na	na	
																												
3	Wood	1.4	1.5	2.5	3.5	4.3	5.1	5.8	6.5	7.2	7.8	8.3	8.9	9.4	9.9	10.3	10.7	11.1	11.5	11.9	12.2	12.5	12.9	na	na	na	na	
																												
	Metal	1.2	1.3	1.9	2.4	2.8	3.1	3.3	3.5	3.7	3.8	4	4.1	4.2	4.3	4.4	4.4	4.5	4.6	4.6	4.7	4.7	4.8	na	na	na	na	
																												
3.5	Wood	1.4	1.5	2.6	3.5	4.4	5.2	6	6.7	7.4	8.1	8.7	9.3	9.8	10.4	10.9	11.3	11.8	12.2	12.6	13	13.4	13.8	14.1	14.5	14.8	15.1	
																												
	Metal	1.2	1.3	2	2.5	2.9	3.2	3.5	3.8	4	4.2	4.3	4.5	4.6	4.7	4.8	4.9	5	5.1	5.1	5.2	5.2	5.3	5.4	5.4	5.4	5.5	
																												
4	Wood	1.4	1.6	2.6	3.6	4.5	5.3	6.1	6.9	7.6	8.3	9	9.6	10.2	10.8	11.3	11.9	12.4	12.8	13.3	13.7	14.2	14.6	14.9	15.3	15.7	16	
																												
	Metal	1.2	1.3	2	2.6	3	3.4	3.7	4	4.2	4.5	4.6	4.8	5	5.1	5.2	5.3	5.4	5.5	5.6	5.7	5.8	5.8	5.9	5.9	6	6	
																												
4.5	Wood	1.4	1.6	2.6	3.6	4.5	5.4	6.2	7.1	7.8	8.5	9.2	9.9	10.5	11.2	11.7	12.3	12.8	13.3	13.8	14.3	14.8	15.2	15.7	16.1	16.5	16.9	
																												
	Metal	1.2	1.3	2.1	2.6	3.1	3.5	3.9	4.2	4.5	4.7	4.9	5.1	5.3	5.4	5.6	5.7	5.8	5.9	6	6.1	6.2	6.3	6.4	6.4	6.5	6.6	
																												
5	Wood	1.4	1.6	2.6	3.6	4.6	5.5	6.3	7.2	8	8.7	9.4	10.1	10.8	11.5	12.1	12.7	13.2	13.8	14.3	14.8	15.3	15.8	16.3	16.7	17.2	17.6	
																												
	Metal	1.2	1.4	2.1	2.7	3.2	3.7	4.1	4.4	4.7	5	5.2	5.4	5.6	5.8	5.9	6.1	6.2	6.3	6.5	6.6	6.7	6.8	6.8	6.9	7	7.1	
																												
5.5	Wood	1.4	1.6	2.6	3.6	4.6	5.5	6.4	7.3	8.1	8.9	9.6	10.3	11	11.7	12.4	13	13.6	14.2	14.7	15.3	15.8	16.3	16.8	17.3	17.8	18.2	
																												
	Metal	1.3	1.4	2.1	2.8	3.3	3.8	4.2	4.6	4.9	5.2	5.4	5.7	5.9	6.1	6.3	6.4	6.6	6.7	6.8	7	7.1	7.2	7.3	7.4	7.5	7.6	

TABLE B-13 
Assembly U-Factors for Metal Building Walls
Insulation System	Rated R-Value of Insulation	Total Rated R-Value of Insulation	Overall U-Factor for Entire Base Wall Assembly	Overall U-Factor for Assembly of Base Wall Plus Continuous Insulation (uninterrupted by framing)

Rated R-Value of Continuous Insulation	
				R-5.6	R-11.2	R-16.8	R-22.4	R-28.0	R-33.6	
Single Layer of  Mineral Fiber	
										
	None	0	1.18	0.161	0.086	0.059	0.045	0.036	0.03	
										
	R-6	6	0.184	0.091	0.06	0.045	0.036	0.03	0.026	
										
	R-10	10	0.134	0.077	0.054	0.041	0.033	0.028	0.024	
										
	R-11	11	0.123	0.073	0.052	0.04	0.033	0.028	0.024	
										
	R-13	13	0.113	0.069	0.05	0.039	0.032	0.027	0.024	
										
Double Layer of Mineral Fiber
(Second layer inside of girts)
(Multiple layers are listed in order from inside to outside)	
	R-6+R-13	19	0.07	Na	na	na	na	na	na	
										
	R-10+R-13	23	0.061	Na	na	na	na	na	na	
										
	R-13+R-13	26	0.057	Na	na	na	na	na	na	
										
	R-19+R-13	32	0.048	Na	na	na	na	na	na	

TABLE B-14 
Assembly U-Factors for Steel Frame Walls
Framing Type and Spacing Width (actual depth)	Cavity Insulation R-Value: Rated/ (effective installed [see Table A-21])	Overall U-Factor for Entire Base Wall Assembly	Overall U-Factor for Assembly of Base Wall Plus Continuous Insulation (uninterrupted by framing), Rated R-Value of Continuous Insulation	
			R-1.0	R-2.0	R-3.0	R-4.0	R-5.0	R-6.0	R-7.0	R-8.0	R-9.0	R-10.0	R-11.0	R-12.0	R-13.0	R-15.0	R-15.0	R-20.0	R-25.0	R-30.0	R-35.0	R-40.0	
Steel Framing at 16 in. OC	
(3.5 in. depth)	None(0.0)	0.352	0.26	0.207	0.171	0.146	0.128	0.113	0.102	0.092	0.084	0.078	0.072	0.067	0.063	0.059	0.056	0.044	0.036	0.03	0.026	0.023	
																							
	R-11(5.5)	0.132	0.117	0.105	0.095	0.087	0.08	0.074	0.069	0.064	0.06	0.057	0.054	0.051	0.049	0.046	0.044	0.036	0.031	0.027	0.024	0.021	
																							
	R-13(6.0)	0.124	0.111	0.1	0.091	0.083	0.077	0.071	0.066	0.062	0.059	0.055	0.052	0.05	0.048	0.045	0.043	0.036	0.03	0.026	0.023	0.021	
																							
	R-15(6.4)	0.118	0.106	0.096	0.087	0.08	0.074	0.069	0.065	0.061	0.057	0.054	0.051	0.049	0.047	0.045	0.043	0.035	0.03	0.026	0.023	0.021	
																							
(6.0 in. depth)	R-19(7.1)	0.109	0.099	0.09	0.082	0.076	0.071	0.066	0.062	0.058	0.055	0.052	0.05	0.047	0.045	0.043	0.041	0.034	0.029	0.026	0.023	0.02	
																							
	R-21(7.4)	0.106	0.096	0.087	0.08	0.074	0.069	0.065	0.061	0.057	0.054	0.051	0.049	0.047	0.045	0.043	0.041	0.034	0.029	0.025	0.022	0.02	
																							
Steel Framing at 24 in. OC	
(3.5 in. depth)	None(0.0)	0.338	0.253	0.202	0.168	0.144	0.126	0.112	0.1	0.091	0.084	0.077	0.072	0.067	0.063	0.059	0.056	0.044	0.036	0.03	0.026	0.023	
																							
	R-11(6.6)	0.116	0.104	0.094	0.086	0.079	0.073	0.068	0.064	0.06	0.057	0.054	0.051	0.048	0.046	0.044	0.042	0.035	0.03	0.026	0.023	0.021	
																							
	R-13(7.2)	0.108	0.098	0.089	0.082	0.075	0.07	0.066	0.062	0.058	0.055	0.052	0.049	0.047	0.045	0.043	0.041	0.034	0.029	0.025	0.023	0.02	
																							
	R-15(7.8)	0.102	0.092	0.084	0.078	0.072	0.067	0.063	0.059	0.056	0.053	0.05	0.048	0.046	0.044	0.042	0.04	0.034	0.029	0.025	0.022	0.02	
(6.0 in. depth)																							
	R-19(8.6)	0.094	0.086	0.079	0.073	0.068	0.064	0.06	0.057	0.054	0.051	0.048	0.046	0.044	0.042	0.041	0.039	0.033	0.028	0.025	0.022	0.02	
																							
	R-21(9.0)	0.09	0.083	0.077	0.071	0.066	0.062	0.059	0.055	0.052	0.05	0.048	0.045	0.043	0.042	0.04	0.038	0.032	0.028	0.024	0.022	0.02	

Table B-15 
Assembly U-Factors for Wood Frame Walls

	Framing Type and Spacing Width (actual Depth)	Cavity Insulation R-Value: Rated/(effective stalled [see Table A-24])	Overall U-Factor for Entire Bas Wall	Overall U-Factor for Assembly of Base Wall Plus Continuous Insulation (uninterrupted by framing)
Rated R-Value of Continuous Insulation	
				R-1.0	E-2.0	R-3.0	R-4.0	R-5.0	R-6.0	R-7.0	R-8.0	R-9.0	R-10.0	R-11.0	R-12.0	R-13.0	R-14.0	R-15.0	R-20.0	R-25.0	R-30.0	R-35.0	R-40.0	
	Wood Studs at 16 in. OC	
	(3.5 in. depth)	None(0.0)	0.292	0.223	0.181	0.152	0.132	0.116	0.104	0.094	0.086	0.079	0.073	0.068	0.064	0.06	0.056	0.053	0.042	0.035	0.03	0.026	0.023	
																								
		R-11(11.0)	0.096	0.087	0.079	0.073	0.068	0.063	0.059	0.056	0.053	0.05	0.048	0.046	0.044	0.042	0.04	0.038	0.032	0.028	0.024	0.022	0.02	
																								
		R-13(13.0)	0.089	0.08	0.074	0.068	0.063	0.059	0.056	0.053	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.037	0.031	0.027	0.024	0.021	0.019	
																								
		R-15(15.0)	0.083	0.075	0.069	0.064	0.06	0.056	0.053	0.05	0.047	0.045	0.043	0.041	0.039	0.038	0.036	0.035	0.03	0.026	0.023	0.02	0.019	
																								
	(5.5 in. depth)																							
		R-19(18.0)	0.067	0.062	0.058	0.054	0.051	0.048	0.046	0.044	0.042	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.027	0.024	0.021	0.019	0.018	
																								
		R-21(21.0)	0.063	0.058	0.054	0.051	0.048	0.045	0.043	0.041	0.039	0.038	0.036	0.035	0.034	0.032	0.031	0.03	0.026	0.023	0.021	0.019	0.017	
																								
	+R-10 headers)																							
		R-19(18.0)	0.063	0.059	0.055	0.052	0.049	0.047	0.045	0.043	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.031	0.027	0.024	0.021	0.019	0.017	
																								
		R-21(21.0)	0.059	0.055	0.051	0.049	0.046	0.044	0.042	0.04	0.038	0.037	0.035	0.034	0.033	0.032	0.031	0.03	0.026	0.023	0.02	0.018	0.017	
																								
	Wood Studs at 24 in.OC	
	(3.5 in. depth)	None(0.0)	0.298	0.227	0.183	0.154	0.133	0.117	0.105	0.095	0.086	0.079	0.074	0.068	0.064	0.06	0.057	0.054	0.042	0.035	0.03	0.026	0.023	
																								
		R-11(11.0)	0.094	0.085	0.078	0.072	0.067	0.062	0.059	0.055	0.052	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.032	0.027	0.024	0.022	0.019	
																								
		R-13(13.0)	0.086	0.078	0.072	0.067	0.062	0.058	0.055	0.052	0.049	0.047	0.045	0.043	0.041	0.039	0.038	0.036	0.031	0.026	0.023	0.021	0.019	
																								
		R-15(15.0)	0.08	0.073	0.067	0.062	0.058	0.055	0.052	0.049	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.029	0.026	0.023	0.02	0.018	
																								
	(5.5 in. depth)																							
		R-19(18.0)	0.065	0.06	0.056	0.053	0.05	0.047	0.045	0.043	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.032	0.027	0.024	0.021	0.019	0.018	
																								
		R-21(21.0)	0.06	0.056	0.052	0.049	0.046	0.044	0.042	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.026	0.023	0.02	0.018	0.017	
																								
	(+ R-10 headers)																							
		R-19(18.0)	0.062	0.058	0.054	0.051	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.034	0.033	0.032	0.031	0.027	0.024	0.021	0.019	0.017	
																								
		R-21(21.0)	0.057	0.053	0.05	0.047	0.045	0.043	0.041	0.039	0.037	0.036	0.035	0.033	0.032	0.031	0.03	0.029	0.025	0.023	0.02	0.018	0.017	

TABLE B-16 
Assembly C-Factors for Below-Grade Walls
Framing Type & Depth

	Rated R-Value of Insulation Alone	Specified C-Factors (wall only, without soil & air films)	
No Framing	0	1.140	
Exterior Insulation continuous and uninterrupted by framing	
No Framing	5.0	0.170	
No Framing	7.5	0.119	
No Framing	10.0	0.092	
No Framing	12.5	0.075	
No Framing	15.0	0.063	
No Framing	17.5	0.054	
No Framing	20.0	0.048	
No Framing	25.0	0.039	
No Framing	30.0	0.032	
No Framing	35.0	0.028	
No Framing	40.0	0.025	
No Framing	45.0	0.022	
No Framing	50.0	0.020	
Continuous Framing at 24 in. OC horizontally	
3.5 in	11.0	0.182	
3.5 in	13.0	0.174	
3.5 in	15.0	0.168	
5.5 in	19.0	0.125	
5.5 in	21.0	0.120	
1 in metal clips at 24 in. OC horizontally & 16 in. vertically	
1 in	3.8	0.233	
1 in	5.0	0.201	
1 in	5.6	0.189	
1.5 in	5.7	0.173	
1.5 in	7.5	0.147	
1.5 in	8.4	0.138	
2 in	7.6	0.138	
2 in	10.0	0.116	
2 in	11.2	0.108	
2.5 in	9.5	0.114	
2.5 in	12.5	0.096	
2.5 in	14.0	0.089	
3 in	11.4	0.098	
3 in	15.0	0.082	
3 in	16.8	0.076	
3.5 in	13.3	0.085	
3.5 in	17.5	0.071	
3.5 in	19.6	0.066	
4 in	15.2	0.076	
4 in	20.0	0.063	
4 in	22.4	0.058	

TABLE B-17 
Effective Insulation/Framing Layer R-Values for Wall Insulation Installed Between Steel Framing
Nominal Depth of Cavity (in.)	Actual Depth of Cavity (in.)	Rated R-Value of Airspace or Insulation	Effective Framing/ Cavity R-Value at 16 in. on center	Effective Framing/Cavity at 24 in. on center	
Empty cavity, no insulation	
4	3.5	R-0.91	0.79	0.91	
					
Insulated Cavity	
4	3.5	R-11	5.5	6.6	
4	3.5	R-13	6	7.2	
4	3.5	R-15	6.4	7.8	
6	6	R-19	7.1	8.6	
6	6	R-21	7.4	9	
8	8	R-25	7.8	9.6	

2.3 Opaque Doors. All opaque doors with U-factors determined, certified, and labeled in accordance with NFRC 100 as specified in B1.1.3 shall be assigned those U-factors. Unlabeled opaque doors shall be assigned the following U-factors:
a.	Uninsulated single-layer metal swinging doors or nonswinging doors, including single-layer uninsulated access hatches and uninsulated smoke vents: 1.45
b.	Uninsulated double-layer metal swinging doors or nonswinging doors, including double-layer uninsulated access hatches and uninsulated smoke vents: 0.70
c.	Insulated metal swinging doors, including fire-rated doors, insulated access hatches, and insulated smoke vents: 0.50
d.	Wood doors, minimum nominal thickness of 1 3/4 in., including panel doors with minimum panel thickness of 1 1/8 in., solid core flush doors, and hollow core flush doors: 0.50.
e.	Any other wood door: 0.60 No credit shall be given for any other features, including thermal breaks in metal door slabs (the operable part of the door) or frames, other than as determined in accordance with B1.1.3.

2.4 Roofs
2.4.1 General. The buffering effect of suspended ceilings or attic spaces shall not be included in U-factor calculations.

2.4.2 Roofs with Insulation Entirely Above Deck. U-factors for roofs with insulation entirely above deck shall be taken from Table B-19. It is not acceptable to use these U-factors if the insulation is not entirely above deck or not continuous. For the purpose of B1.4.2, the base assembly is continuous insulation over a structural deck. The U-factor includes R-0.17 for exterior air film, R-0 for metal deck, and R-0.61 for interior air film heat flow up. Added insulation is continuous and uninterrupted by framing. The framing factor is zero.

2.4.3 Metal Building Roofs. U-factors for metal building roofs shall be taken from Table B-20. It is not acceptable to use these U-factors if additional insulated sheathing is not continuous. For the purpose of B1.4.2, the base assembly is a roof where the insulation is draped over the steel structure (purlins) and then compressed when the metal spanning members are attached to the steel structure (purlins). Additional assemblies include continuous insulation, uncompressed and uninterrupted by framing.

2.4.4 Attic Roofs with Wood Joists. U-factors for attic roofs with wood joists shall be taken from Table B-21. It is not acceptable to use these U-factors if the framing is not wood. For attic roofs with steel joists, see B2.4.5. For the purpose of B1.4.2, the base attic roof assembly is a roof with a nominal 4 in. deep wood as the lower chord of a roof truss or ceiling joist. The ceiling is attached directly to the lower chord of the truss and the attic space above is ventilated. Insulation is located directly on top of the ceiling, first filling the cavities between the wood and then later covering both the wood and cavity areas. No credit is given for roofing materials. The single-rafter roof is similar to the base attic roof, with the key difference being that there is a single, deep rafter to which both the roof and the ceiling are attached. The heat flow path through the rafter is calculated to be the same depth as the insulation. The U-factor includes R-0.46 for semi-exterior air film, R-0.56 for 0.625 in. gypsum board, and R-0.61 for interior air film heat flow up. U-factors are provided for the following configurations:
a. Attic roof, standard framing: insulation is tapered around the perimeter with resultant decrease in thermal resistance. Weighting factors are 85% full-depth insulation, 5% half-depth insulation, and 10% joists.
b. Attic roof, advanced framing: full and even depth of insulation extending to the outside edge of exterior walls. Weighting factors are 90% full-depth insulation and 10% joists.
c. Single-rafter roof: an attic roof where the roof sheathing and ceiling are attached to the same rafter. Weighting factors are 90% full-depth insulation and 10% joists.

2.4.5 Attic Roofs with Steel Joists. U-factors for attic roofs with steel joists shall be taken from Table B-22. It is acceptable to use these U-factors for any attic roof with steel joists. For the purpose of B1.4.2, the base assembly is a roof supported by steel joists with insulation between the joists. The assembly represents a roof in many ways similar to a roof with insulation entirely above deck and a metal building roof. It is distinguished from the metal building roof category in that there is no metal exposed to the exterior. It is distinguished from the roof with insulation entirely above deck in that the insulation is located below the deck and is interrupted by metal trusses that provide thermal bypasses to the insulation. The U-factor includes R-0.17 for exterior air film, R-0 for metal deck, and R-0.61 for interior air film heat flow up. The performance of the insulation/framing layer is calculated using the values in Table B-18.

TABLE B-18 
Effective Insulation/Framing Layer R-Values for Roof and
Floor Insulation Installed Between Metal Framing (4 ft on center)
Rated R-Value of Insulation	Correction Factor	Framing/Cavity R-Value	
0	1	0	
			
4	0.97	3.88	
			
5	0.96	4.8	
			
8	0.94	7.52	
			
10	0.92	9.2	
			
11	0.91	10.01	
			
12	0.9	10.8	
			
13	0.9	11.7	
			
15	0.88	13.2	
			
16	0.87	13.92	
			
19	0.86	16.34	
			
20	0.85	17	
			
21	0.84	17.64	
			
24	0.82	19.68	
			
25	0.81	20.25	
			
30	0.79	23.7	
			
35	0.76	26.6	
			
38	0.74	28.12	
			
40	0.73	29.2	
			
45	0.71	31.95	
			
50	0.69	34.5	
			
55	0.67	36.85	

TABLE B-19
Assembly U-Factors for Roofs with Insulation
Entirely Above Deck

Rated R-Value of 
Insulation Alone	Overall U-Factor for
Entire Assembly	
R-0
R-1
R-2
R-3
R-4
R-5	U-1.282
U-0.562
U-0.360
U-0.265
U-0.209
U-0.173	
R-6
R-7
R-8
R-9
R-10	U-0.147
U-0.129
U-0.114
U-0.102
U-0.093	
R-11
R-12
R-13
R-14
R-15	U-0.085
U-0.078
U-0.073
U-0.068
U-0.063	
R-16
R-17
R-18
R-19
R-20	U-0.060
U-0.056
U-0.053
U-0.051
U-0.048	
R-21
R-22
R-23
R-24
R-25	U-0.046
U-0.044
U-0.042
U-0.040
U-0.039	
R-26
R-27
R-28
R-29
R-30	U-0.037
U-0.036
U-0.035
U-0.034
U-0.032	
R-35	U- 0.028	
R-40	U-0.025	
R-45	U-0.020	
R-50	U-0.020	
R-55	U-0.018	
R-60	U-0.016	

TABLE B-20 
Assembly U-Factors for Metal Building Roofs

Insulation
System	Rated R-Valueof
Insulation	Total rated
R-value of
Insulation	Overall U-Factor for Entire Base Roof Assembly	Overall U-Factor for Assembly of Base Roof Plus Continuous Insulation
(uninterrupted by framing
Rated R-Value of Continuous Insulation	
				R-5.6	R-11.2	R-16.8	R-22.4	R-28.0	R-33.6	
Standing Seam Roofs with Thermal Blocks
Single                None                0                     1.280                 0.162         0.087      0.059        0.045        0.036       0.030
Layer                  R-6                  6                     0.167                 0.086         0.058      0.044        0.035        0.029       0.025
                          R-10               10                     0.097                 0.063         0.046      0.037         0.031       0.026       0.023
                          R-11               11                     0.092                 0.061         0.045      0.036         0.030       0.026       0.022
                          R-13               13                     0.083                 0.057         0.043      0.035         0.029       0.025       0.022
                          R-16               16                     0.072                 0.051         0.040      0.033         0.028       0.024       0.021
                          R-19               19                     0.065                 0.048         0.038      0.031         0.026       0.023       0.020	
Double              R-10 + R-10   20                     0.063                 0.047          0.037     0.031         0.026       0.023       0.020
Layer                R-10 + R-11    21                     0.061                 0.045          0.036    0.030         0.026        0.023       0.020
                         R-11 + R-11    22                     0.060                 0.045          0.036    0.030         0.026        0.022       0.020
                         R-10 + R-13    23                     0.058                 0.044          0.035    0.029         0.025        0.022       0.020
                         R-11 + R-13    24                     0.057                 0.043          0.035    0.029         0.025        0.022       0.020
                         R-13 + R-13    26                     0.055                 0.042          0.034    0.029          0.025       0.022       0.019
                         R-10 + R-19    29                     0.052                 0.040          0.033    0.028          0.024       0.021       0.019
                         R-11 + R-19     30                    0.051                 0.040          0.032    0.027          0.024       0.021       0.019
                         R-13 + R-19     32                    0.049                 0.038          0.032    0.027          0.023       0.021       0.019
                         R-16 + R-19     35                    0.047                 0.037          0.031    0.026          0.023       0.020       0.018
                         R-19 + R-19     38                    0.046                 0.037          0.030    0.026          0.023       0.020       0.018
(Multiple R-values are listed in order from inside to outside)
	
Screw Down Roofs
                         R-10                10                    0.153                  0.082          0.056    0.043         0.035        0.029       0.025
                         R-11                11                    0.139                  0.078          0.054    0.042         0.034        0.028       0.025
                         R-13                13                    0.130                  0.075          0.053    0.041         0.033        0.028       0.024	
Filled Cavity with Thermal Blocks
                         R19 + R-10     29                    0.041                  0.033          0.028     0.024        0.021        0.0198     0.017
(Multiple R-values are listed in order from inside to outside)	

TABLE B-21 
Assembly U-Factors for Attic Roofs
with Wood Joists

Rated R-Value of
Insulation Alone
	Overall U-Factor for
Entire Assembly	
Wood-framed attic, 
standard framing
None
R-11
R-13
R-19
R-30
R-38
R-49
R-60
R-71
R-82
R-93
R-104
R-115
R-126	
0.613
0.091
0.081
0.053
0.034
0.027
0.021
0.017
0.015
0.013
0.011
0.010
0.009
0.008	
Wood-framed attic, advanced framing
None
R-11
R-13
R-19
R-30
R-38
R-49
R-60
R-71
R-82
R-93
R-104
R-115
R-126	
0.613
0.088
0.078
0.051
0.032
0.026
0.020
0.016
0.014
0.012
0.011
0.010
0.009
0.008	
Wood joists, single rafter roof
None
R-11
R-13
R-15
R-19
R-21
R-25
R-30
R-38	
0.417
0.088
0.078
0.071
0.055
0.052
0.043
0.036
0.028	

TABLE B-22
Assembly U-Factors for Attic Roofs
with Steel Joists (4.0 ft on center)

Rated R-Value of
Insulation Area	Overall U-Factor for
Entire Assembly	
R-0
R-4
R-5
R-8
R-10	U-1.282
U-0.215
U-0.179
U-0.120
U-0.100	
R-11
R-12
R-13
R-15
R-16
R-19	U-0.093
U-0.086
U-0.080
U-0.072
U-0.068
U-0.058	
R-20
R-21
R-24
R-25
R-30	U-0.056
U-0.054
U-0.049
U-0.048
U-0.041	
R-35
R-38
R-40
R-45
R-50
R-55	U-0.037
U-0.035
U-0.033
U-0.031
U-0.028
U-0.027	

2.5 Floors

2.5.1 General. The buffering effect of crawl spaces or parking garages shall not be included in U-factor calculations. See B2.5.5 for slab-on-grade floors.

2.5.2 Mass Floors. U-factors for mass floors shall be taken from Table B-23. It is not acceptable to use these U-factors if the insulation is not continuous. For the purpose of B1.4.2, the base assembly is continuous insulation over or under a solid concrete floor. The U-factor includes R-0.92 for interior air film—heat flow down, R-1.23 for carpet and rubber pad, R-0.50 for 8 in. concrete, and R-0.46 for semi-exterior air film. Added insulation is continuous and uninterrupted by framing. Framing factor is zero.

2.5.3 Steel Joist Floors. U-factors for steel joist floors shall be taken from Table B-24. It is acceptable to use these U-factors for any steel joist floor. For the purpose of B1.4.2, the base assembly is a floor where the insulation is either placed between the steel joists or is sprayed on the underside of the floor and the joists. In both cases, the steel provides a thermal bypass to the insulation. The U-factor includes R-0.92 for interior air film—heat flow down, R-1.23 for carpet and pad, R-0.25 for 4 in. concrete, R-0 for metal deck, and R-0.46 for semi-exterior air film. The performance of the insulation/framing layer is calculated using the values in Table B-18.

2.5.4 Wood-Framed Floors. U-factors for wood-framed floors shall be taken from Table B-25. It is not acceptable to use these U-factors if the framing is not wood. For the purpose of B1.4.2, the base assembly is a floor attached directly to the top of the wood joist and with insulation located directly below the floor, with a ventilated airspace below the insulation. The heat flow path through the joist is calculated to be the same depth as the insulation. The U-factor includes R-0.92 for interior air film—heat flow down, R-1.23 for carpet and pad, R-0.94 for 0.75 in. wood subfloor, and R-0.46 for semi-exterior air film. The weighting factors are 91% insulated cavity and 9% framing.

2.5.5 Slab-on-Grade Floors. F-factors for slab-on-grade floors shall be taken from Table B-26. These F-factors are acceptable for all slab-on-grade floors. For the purpose of B1.4.2, the base assembly is a slab floor of 6 in. concrete poured directly on to the earth, the bottom of the slab is at grade line, and soil conductivity is 0.75 Btu/h·ft2·oF. In contrast to the U-factor for floors, the F-factor for slab-on-grade floors is expressed per lineal foot of building perimeter. F-factors are provided for unheated slabs and for heated slabs. Unheated slab-on-grade floors do not have heating elements, and heated slab-on-grade floors do have heating elements within or beneath the slab. F-factors are provided for three insulation configurations:
a. Horizontal insulation: continuous insulation is applied directly to the underside of the slab and extends inward horizontally from the perimeter for the distance specified or continuous insulation is applied downward from the top of the slab and then extends horizontally to the interior or the exterior from the perimeter for the distance specified.
b. Vertical insulation: continuous insulation is applied directly to the slab exterior, extending downward from the top of the slab for the distance specified.
c. Fully insulated slab: continuous insulation extends downward from the top of the slab and along the entire perimeter and completely covers the entire area under the slab.

TABLE B-23 
Assembly U-Factors for Mass Floors
Framing Type & Spacing Width (actual depth)	Cavity Insulation R-Value:Rated/ (effective installed)	Overall U-Factor for Entire Base Wall Assembly	Overall U-Factor for Assembly of Base Floor Plus Continuous Insulation (uninterrupted by framing)
Rated R-Value of Continuous Insulation	
			R-1.0	R-2.0	R-3.0	R-4.0	R-5.0	R-6.0	R-7.0	R-8.0	R-9.0	R-10.0	R-11.0	R-12.0	R-13.0	R-14.0	R-15.0	R-20.0	R-25.0	R-30.0	R-35.0	R-40.0	
Concrete Floor with Rigid Foam	
	None(0.0)	0.322	0.243	0.196	0.164	0.141	0.123	0.11	0.099	0.09	0.083	0.076	0.071	0.066	0.062	0.058	0.055	0.043	0.036	0.03	0.026	0.023	
																							
Concrete Floor with Pinned Boards	
	R-4.2(4.2)	0.137	0.121	0.108	0.097	0.089	0.081	0.075	0.07	0.065	0.061	0.058	0.055	0.052	0.049	0.047	0.045	0.037	0.031	0.027	0.024	0.021	
																							
	R-6.3(6.3)	0.107	0.096	0.088	0.081	0.075	0.07	0.065	0.061	0.058	0.054	0.052	0.049	0.047	0.045	0.043	0.041	0.034	0.029	0.025	0.023	0.02	
																							
	R-8.3(8.3)	0.087	0.08	0.074	0.069	0.065	0.061	0.057	0.054	0.051	0.049	0.047	0.045	0.043	0.041	0.039	0.038	0.032	0.027	0.024	0.022	0.019	
																							
	R-10.4(10.4)	0.074	0.069	0.064	0.06	0.057	0.054	0.051	0.049	0.046	0.044	0.042	0.041	0.039	0.038	0.036	0.035	0.03	0.026	0.023	0.021	0.019	

	R-12.5(12.5)	0.064	0.06	0.057	0.054	0.051	0.048	0.046	0.044	0.042	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.028	0.025	0.022	0.02	0.018	

	R-14.6(14.6)	0.056	0.053	0.051	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.034	0.033	0.032	0.031	0.027	0.023	0.021	0.019	0.017	

	R-16.7(16.7)	0.051	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.034	0.032	0.031	0.03	0.03	0.029	0.025	0.022	0.02	0.018	0.017	
																							
Concrete Floor with Spray-on Insulation	
(1in.)	R-4(4.0)	0.141	0.123	0.11	0.099	0.09	0.083	0.076	0.071	0.066	0.062	0.058	0.055	0.052	0.05	0.047	0.045	0.037	0.031	0.027	0.024	0.021	
																							
(2in.)	R-8(8.0)	0.09	0.083	0.076	0.071	0.066	0.062	0.058	0.055	0.052	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.032	0.028	0.024	0.022	0.02	
																							
(3in.)	R-12(12.0)	0.066	0.062	0.058	0.055	0.052	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.037	0.036	0.034	0.033	0.028	0.025	0.022	0.02	0.018	
																							
(4in.)	R-16(16.0)	0.052	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.029	0.026	0.023	0.02	0.018	0.017	
																							
(5in.)	R-20(20.0)	0.043	0.041	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.028	0.027	0.026	0.023	0.021	0.019	0.017	0.016	
																							
(6in.)	R-24(24.0)	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.028	0.027	0.026	0.026	0.025	0.024	0.024	0.021	0.019	0.018	0.016	0.015	

TABLE B-24 
Assembly U-Factors for Steel Joist Floors
Framing Type and Spacing Width (actual depth)	Cavity Insulation R-Value: Rated/ (effective installed [see Table A-20])	Overall U-Factor for Entire Base Wall Assembly

	Overall U-Factor for Assembly of Base Floor Plus Continuous Insulation (uninterrupted by framing)
Rated R-Value of Continuous Insulation	
			R-1.0	R-2.0	R-3.0	R-4.0	R-5.0	R-6.0	R-7.0	R-8.0	R-9.0	R-10.0	R-11.0	R-12.0	R-13.0	R-14.0	R-15.0	R-20.0	R-25.0	R-30.0	R-35.0	R-40.0	
Steel Joist Floor with Rigid Foam	
	None(0.0)	0.35	0.259	0.206	0.171	0.146	0.127	0.113	0.101	0.092	0.084	0.078	0.072	0.067	0.063	0.059	0.056	0.044	0.036	0.03	0.026	0.023	
																							
Steel Joist Floor with Spray-on Insulation	
(1in.)	R-4(3.88)	0.148	0.129	0.114	0.103	0.093	0.085	0.078	0.073	0.068	0.064	0.06	0.056	0.053	0.051	0.048	0.046	0.037	0.032	0.027	0.024	0.021	
																							
(2in.)	R-8(7.52)	0.096	0.088	0.081	0.075	0.07	0.065	0.061	0.058	0.054	0.052	0.049	0.047	0.045	0.043	0.041	0.039	0.033	0.028	0.025	0.022	0.02	
																							
(3in.)	R-12(10.8)	0.073	0.068	0.064	0.06	0.057	0.054	0.051	0.048	0.046	0.044	0.042	0.041	0.039	0.038	0.036	0.035	0.03	0.026	0.023	0.021	0.019	
																							
(4in.)	R-16(13.92)	0.06	0.056	0.053	0.051	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.034	0.032	0.031	0.027	0.024	0.021	0.019	0.018	
																							
(5in.)	R-20(17.0)	0.05	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.033	0.032	0.031	0.03	0.03	0.029	0.025	0.022	0.02	0.018	0.017	
																							
(6in.)	R-24(19.68)	0.044	0.042	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.027	0.024	0.021	0.019	0.017	0.016	
																							
Steel Joist Floor with Batt Insulation	
	None(0.0)	0.35	0.259	0.206	0.171	0.146	0.127	0.113	0.101	0.092	0.084	0.078	0.072	0.067	0.063	0.059	0.056	0.044	0.036	0.03	0.026	0.023	
																							
	R-11(10.01)	0.078	0.072	0.067	0.063	0.059	0.056	0.053	0.05	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.03	0.026	0.023	0.021	0.019	
																							
	R-13(11.7)	0.069	0.064	0.06	0.057	0.054	0.051	0.049	0.046	0.044	0.042	0.041	0.039	0.038	0.036	0.035	0.034	0.029	0.025	0.022	0.02	0.018	
																							
	R-15(13.2)	0.062	0.059	0.055	0.052	0.05	0.047	0.045	0.043	0.042	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.028	0.024	0.022	0.02	0.018	
																							
	R-19(16.34)	0.052	0.05	0.047	0.045	0.043	0.041	0.04	0.038	0.037	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.026	0.023	0.02	0.018	0.017	
																							
	R-21(17.64)	0.049	0.047	0.044	0.043	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.025	0.022	0.02	0.018	0.017	
																							
	R-25(20.25)	0.043	0.041	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.028	0.027	0.026	0.023	0.021	0.019	0.017	0.016	
																							
	R-30C(23.70)	0.038	0.036	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.027	0.026	0.025	0.025	0.024	0.021	0.019	0.018	0.016	0.015	
																							
	R-30(23.7)	0.038	0.036	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.027	0.026	0.025	0.025	0.024	0.021	0.019	0.018	0.016	0.015	
																							
	R-38C(28.12)	0.032	0.031	0.03	0.029	0.029	0.028	0.027	0.026	0.026	0.025	0.024	0.024	0.023	0.023	0.022	0.022	0.02	0.018	0.016	0.015	0.014	
																							
	R-38(28.12)	0.032	0.031	0.03	0.029	0.029	0.028	0.027	0.026	0.026	0.025	0.024	0.024	0.023	0.023	0.022	0.022	0.02	0.018	0.016	0.015	0.014	

TABLE B-25 
Assembly U-Factors for Wood Joist Floors
Framing Type & Spacing Width (actual Depth)	Cavity Insulation R-Value: Rated/ (effective installed)	Overall U-Factor for Entire Base Wall Assembly	Overall U-Factor for Assembly of Base Floor Plus Continuous Insulation (uninterrupted by framing)
Rated R-Value of Continuous Insulation	
			R-1.0	R-2.0	R-3.0	R-4.0	R-5.0	R-6.0	R-7.0	R-8.0	R-9.0	R-10.0	R-11.0	R-12.0	R-13.0	R-14.0	R-15.0	R-20.0	R-25.0	R-30.0	R-35.0	R-40.0	
Wood Joists	
(5.5in.)	None(0.0)	0.282	0.22	0.18	0.153	0.132	0.117	0.105	0.095	0.087	0.08	0.074	0.069	0.064	0.06	0.057	0.054	0.042	0.035	0.03	0.026	0.023	
																							
	R-11(11.0)	0.074	0.069	0.064	0.06	0.057	0.054	0.051	0.048	0.046	0.044	0.042	0.04	0.039	0.037	0.036	0.035	0.03	0.026	0.023	0.02	0.019	
																							
	R-13(13.0)	0.066	0.062	0.058	0.055	0.052	0.049	0.047	0.045	0.043	0.041	0.039	0.038	0.036	0.035	0.034	0.033	0.028	0.025	0.022	0.02	0.018	
																							
	R-15(15.0)	0.06	0.057	0.053	0.05	0.048	0.046	0.044	0.042	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.027	0.024	0.021	0.019	0.017	
																							
	R-19(18.0)	0.051	0.048	0.046	0.044	0.042	0.04	0.038	0.037	0.036	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.025	0.022	0.02	0.018	0.017	
																							
	R-21(21.0)	0.046	0.043	0.042	0.04	0.038	0.037	0.035	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.027	0.023	0.021	0.019	0.017	0.016	
																							
(7.25in.)	R-25(25.0)	0.039	0.037	0.036	0.035	0.033	0.032	0.031	0.03	0.029	0.028	0.028	0.027	0.026	0.025	0.025	0.024	0.022	0.019	0.018	0.016	0.015	
																							
	R-30C(30.0)	0.034	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.026	0.026	0.025	0.024	0.024	0.023	0.023	0.022	0.02	0.018	0.016	0.015	0.014	

(9.25in.)	R-30(30.0)	0.033	0.032	0.031	0.03	0.029	0.028	0.027	0.027	0.026	0.025	0.024	0.024	0.023	0.023	0.022	0.022	0.02	0.018	0.016	0.015	0.014	

(11.25in.)	R-38C(38.0)	0.027	0.026	0.025	0.025	0.024	0.024	0.023	0.022	0.022	0.021	0.021	0.02	0.02	0.02	0.019	0.019	0.017	0.016	0.015	0.014	0.013	

(13.25in.)	R-38938.0)	0.026	0.026	0.025	0.024	0.024	0.023	0.023	0.022	0.022	0.021	0.021	0.02	0.02	0.019	0.019	0.019	0.017	0.016	0.015	0.014	0.013	

TABLE B-26 
Assembly F-Factors for Slab-on-Grade Floors
Insulation Description	Rated R-Value of Insulation	
	R-0	R-5	R-7.5	R-10	R-15	R-20	R-25	R-30	R-35	R-40	R-45	R-50	R-55	
Unheated Slabs	
None	0.73													
														
12 in. horizontal	0.72	0.71	0.71	0.71									
														
24 in. horizontal	0.7	0.7	0.7	0.69									
														
36in. Horizontal	0.68	0.67	0.66	0.66									
														
48 in. horizontal	0.67	0.65	0.64	0.63									
														
12 in. vertical	0.61	0.6	0.58	0.57	0.567	0.565	0.564						
														
24 in. vertical	0.58	0.56	0.54	0.52	0.51	0.505	0.502						
														
36 in. vertical	0.56	0.53	0.51	0.48	0.472	0.464	0.46						
														
48 in. vertical	0.54	0.51	0.48	0.45	0.434	0.424	0.419						
														
Fully insulated slab	0.46	0.41	0.36	0.3	0.261	0.233	0.213	0.198	0.186	0.176	0.168	0.161	
														
Heated Slabs	
														
None	1.35													
														
12 in. horizontal	1.31	1.31	1.3	1.3									
														
24 in. horizontal	1.28	1.27	1.26	1.25									
														
36 in. horizontal	1.24	1.21	1.2	1.18									
														
48 in. horizontal	1.2	1.17	1.13	1.11									
														
12 in. vertical	1.06	1.02	1	0.98	0.968	0.964	0.961						
														
24 in vertical	0.99	0.95	0.9	0.86	0.843	0.832	0.827						
														
36 in. vertical	0.95	0.89	0.84	0.79	0.762	0.747	0.74						
														
48in. Vertical	0.91	0.85	0.78	0.72	0.688	0.671	0.659						
														
Fully insulated slab	0.74	0.64	0.55	0.44	0.373	0.326	0.296	0.273	0.255	0.239	0.227	0.217	

1.1 General.  

Information on thermal properties, performance of building envelope sections, and components and heat transfer shall be obtained from the 2001 ASHRAE Handbook of Fundamentals.  When the information is not available from this source, the data may be obtained from manufacturer=s information based on laboratory or field test measurements.  
If laboratory or field test measurements are used for envelope heat transmission, they shall be obtained using one of the following test methods:
1.  Guarded Hot Plate:	ASTM C-177-97
2.  Heat Flow Meter:		ASTM C-518-91
3.  Guarded Hot Box:	ASTM C-236-89
4.  Calibrated Hot Box:	ASTM C-976-90
1.1.1 Climate data for determining criteria or compliance values for various cities shall be as provided in the FLA/COM computer program.
1.1.2 The requirements of this Chapter are to be used for determining compliance with this Code.  They are not intended to replace the building loads calculation procedures in the 2001 ASHRAE Handbook of Fundamentals.  Relative to mean radiant temperature, the requirements are based on the assumption that mean radiant temperature is equal to dry-bulb air temperature.  For consideration of mean radiant temperature effects under other conditions, reference should be made to ASHRAE Standard 55-92.  
2.1  Thermal Transmittance
2.1.21  Overall Thermal Transmittance (Uo).  The overall thermal transmittance of the building envelope assembly shall be calculated in accordance with Equation 4-5:

EQUATION 4-5
      				      Uo =   UiAi/Ao
= (U1A1 + U2A2 + ... + UnAn)/Ao
Where:
Uo =	The area-weighted average thermal transmittance of 
the gross area of an envelope assembly; i.e., the 
exterior wall assembly including fenestration and
doors, the roof and ceiling assembly, and the floor
assembly, Btu/(h.ft2.oF).
Ao =	The gross area of the envelope assembly, ft2.
Ui =	The thermal transmittance of each individual path of
the envelope assembly, i.e., the opaque portion of
the fenestration, Btu/(h.ft2.oF).
Ui =	1/Ri (where Ri is the total resistance to heat flow
of an individual path through an envelope assembly).
Ai =	The area of each individual element of the envelope
2.1.2  Fenestration Assemblies.  U-factors (thermal transmittances) of fenestration products (windows, doors and skylights) shall be determined in accordance with the National Fenestration Rating Council 100, Procedure for Determining Fenestration Product U-factors Thermal Properties by an accredited, independent laboratory and labeled and certified by the manufacturer.  Such certified and labeled U-factors shall be accepted for the purposes of determining compliance with the building envelope requirements of this code.
When a manufacturer has not determined product U-factor in accordance with NFRC 100 for a particular product line, compliance with the building envelope requirements of this code shall be determined by assigning such products a default U-factor  in accordance with Tables 4B-1 and 4B-2.  Product features must be verifiable for the product to qualify for the default value associated with those features.  Where the existence of a particular feature cannot be determined with reasonable certainty, the product shall not receive credit for that feature.  Where a composite of materials from two different product types are used, the product shall be assigned the higher U-factor  
Table 4B-1
U-Factor Default Table for Windows, Glazed Doors and Skylights
(Source:  1995 Model Energy Code, Table 102.3a .)

Product Description	
Single Glazed	
Double Glazed	

Metal without Thermal Break	

Operable	
1.30	
0.87	

Fixed	
1.17	
0.69	

Door	
1.26	
0.80	

Skylight	
1.92	
1.30	

Metal with Thermal Break	

Operable	
1.07	
.67	

Fixed	
1.11	
.63	

Door	
1.10	
.66	

Skylight	
1.93	
1.13	

Metal-Clad Wood	

Operable	
0.98	
0.60	

Fixed	
1.05	
0.58	

Door	
0.99	
0.57	

Skylight	
1.50	
0.88	

Wood or Vinyl	

Operable	
0.94	
0.56	

Fixed	
1.04	
0.57	

Door	
0.98	
0.56	

Skylight	
1.47	
0.85	
Glass block assemblies shall have a U-factor value of 0.60.

Table 4B-2
U-Value Default Table for Non-glazed Doors
(Source:  1995 Model Energy Code, Table 102.3b.)
Product Description	With Foam Core	Without Foam Core	
Steel Doors (1 3/4 inches thick)	0.35	0.60	
Wood Doors  (1 3/4 inches thick)	Without Storm Door	With Storm Door	
Panel with 7/16-inch panels	0.54	0.36	
Hollow core flush	0.46	0.32	
Panel with 1 1/8-inch panels	0.39	0.28	
Solid core flush	0.40	0.26	
2.1.3 Walls.  The thermal transmittance of each envelope assembly shall be determined with due consideration of all major series and parallel heat flow paths through the elements of the assembly and film coefficients.  Compression of insulation shall be considered in determining the thermal resistance.
2.1.4  Parallel Path Procedure.  The thermal transmittance of opaque elements of assemblies shall be determined using a series path procedure with correction for the presence of parallel paths within an element of the envelope assembly (such as wall cavities with parallel paths through insulation and studs).
2.1.5  Metal Framing.  For envelope assemblies containing metal framing, the thermal transmittance of the series elements (Ui) shall be determined by using one of the following methods:
1. Results from laboratory or field test measurements.  One of the procedures specified in Section 1.1 of Appendix B shall be used.
2. The zone method described in Chapter 24 of the 1997 ASHRAE Handbook of Fundamentals and the formulas on pages 24.10 through 24.11 shall be used for calculation.
3. The total thermal resistance of the series path shall be calculated in accordance with the following equations: 
Ui = 1/Rt		Equation 6
Rt = Ri + Re		Equation 7
Where:	Rt	= The total resistance of the envelope assembly.
Ri	= The resistance of the series elements (for I = 1 to n)
    excluding the parallel path element(s).
Re	= The equivalent resistance of the element containing
    the parallel path
= (R-value of insulation X Fc).  Values for Fc and
    equivalent resistances shall be taken from Tables 4B-3
    or 4B-4 below.)
TABLE 4B-3
PARALLEL PATH CORRECTION FACTORS--METAL ROOF TRUSSES
SPACED 4 FT. O.C. OR GREATER THAT PENETRATE THE INSULATION
Effective Framing/ Cavity R-Values	Correction Factor  Fc	Equivalent Resistance Re1	
R-0		1.00	R-0	
R-5	0.96	R-4.8	
R-10		0.92		R-9.2	
R-15		0.88	R-13.2	
R-20	0.85	R-17.0	
R-25	0.81	R-20.3	
R-30	0.79	R-23.7	
R-35		0.76	R-26.6	
R-40		0.73		R-29.2	
R-45	0.71	R-32.0	
R-50		0.69		R-34.5	
R-55		0.67		R-36.0	
                1Based on 0.66 inch diameter cross members every one foot.

TABLE 4B-4
PARALLEL PATH CORRECTION FACTORS
METAL FRAMED WALLS WITH STUDS 16 GA. OR LIGHTER
Size of Members	Spacing of Framing, in.	Cavity Insulation,R-Value	Correction Factor, Fc	Equivalent Resistance,  Re	
2 x 4	16" o.c.	R-11	0.50	R-5.0	
		R-13	0.46	R-6.0	
		R-15	0.43	R-6.4	
2 x 4	24" o.c.	R-11	0.60	R-6.6	
		R-13	0.55	R-7.2	
		R-15	0.52	R-7.8	
2 x 6	16" o.c.	R-19	0.37	R-7.1	
		R-21	0.35	R-7.4	
2 x 6	24" o.c.	R-19	0.45	R-8.6	
		R-21	0.43	R-9.0	
2 x 8	16" o.c.	R-25	0.31	R-7.8	
2 x 8	24" o.c.	R-25	0.38	R-9.6	
2.1.6  Non-Metal Framing.  For envelope assemblies containing non-metal framing, the Ui shall be determined from one of the laboratory or field test measurements specified in section 1.1 of Appendix B or from the ASHRAE series-parallel method.  Formulas in Chapter 22, page 22.8 of the 1997 ASHRAE Handbook of Fundamentals shall be used for these calculations.
2.1.7  Below-Grade Components. In all below-grade applications, the thermal performance of the adjacent ground shall be excluded in determining the thermal resistance of the below-grade components.  The R-value required for below-grade walls refers to the overall R-value of the wall assembly excluding air film coefficients and the adjacent ground. 
2.1.8 (A) Roofs/Ceiling.  Method B of FLA/COM uses the following equation and exceptions to determine overall thermal transmittance.
EQUATION 4-8
Overall Thermal Transmittance-Roofs
Uor = 1/(5.3 + 1.8 X 10-3   X HDD65 + 1.3 X 10-3   X CDD65 + 2.6 X 10-4 X CDH80)
EXCEPTIONS:
1. Any building that is heated only shall have an overall thermal transmittance value (Uor) for the gross area of the roof assembly less than or equal to the value determined by Equation 4-8 with CDD65 and CDH80 set equal to zero.
2. Any building that is mechanically cooled only shall have an overall thermal transmittance value (Uor) for the gross area of the roof assembly less than or equal to the value determined by Equation 4-8 with HDD65 set equal to zero.
3. Spaces that are neither heated nor cooled shall have an overall thermal transmittance value (Uor) for the gross area of roof assembly less than or equal to 0.19 Btu/(h.ft2.oF).
2.1.8 (B) Roofs/Ceilings.  For thermal transmittance purposes, when return air ceiling plenums are employed, the roof or ceiling assembly shall not include the resistance of the ceiling or the plenum space as part of the total resistance of the assembly.
2.1.9  Floors.  The thermal resistance of floors shall be in accordance with the criteria of section 2.1.1 of Appendix B.
2.1.10  Slabs.  The R-value and dimensions required for slabs refers only to the insulation materials.  Insulative continuity shall be maintained in the design of slab edge insulation systems.  Continuity shall be maintained from the wall insulation through the slab/wall/footing intersection to the body of the slab edge insulation. 
3.1  Solar Heat Gain Coefficients
The Solar Heat Gain Coefficient (SHGC) for glazed fenestration products (windows, glazed doors and skylights) shall be determined in accordance with National Fenestration Rating Council  200:  Procedure for Determining Fenestration Product Solar Heat Gain Coefficients at Normal Incidence by an accredited, independent laboratory and labeled and certified by the manufacturer.  
When a manufacturer has not determined SHGC in accordance with NFRC 200 for a particular product line, compliance with the building envelope requirements of this code shall be determined by assigning such products a default SHGC in accordance with Table 4B-5  Product features must be verifiable for the product to qualify for the default value associated with those features.  Where the existence of a particular feature cannot be determined with reasonable certainty, the product shall not receive credit for that feature. Where a composite of materials from two different product types are used, the product shall be assigned the higher SHGC.

TABLE 4B-5
SHGC DEFAULT TABLE FOR FENESTRATION

PRODUCT DESCRIPTION	Single Glazed			Double Glazed 	
	Clear	Bronze	Green	Gray	Clear + 
Clear 	Bronze +
Clear	Green +
Clear	Gray +
Clear	
Metal Frames
   Operable
   Fixed	
0.75
0.78	
0.64
0.67	
0.62
0.65	
0.61
0.64	
0.66
0.68	
0.55
0.57	
0.53
0.55	
0.52
0.54	
Nonmetal Frames
   Operable
   Fixed	
0.63
0.75	
0.54
0.64	
0.53
0.62	
0.52
0.61	
0.55
0.66	
0.46
0.54	
0.45
0.53	
0.44
0.52	
4.1 Default Values.
4.1.1 Equipment Power Density
TABLE 4B-6:   AVERAGE RECEPTACLE POWER DENSITIES
Building Type	W/ft.2	
Assembly	0.25	
Office	0.75	
Retail	0.25	
Warehouse	0.10	
School	0.50	
Hotel or Motel	0.25	
Restaurant	0.10	
Health	1.00	
Multifamily	0.75	
4.1.2 Loads From Occupants.  Heat Generation:  Btu/person-hour:  230 sensible and 190 latent.	
TABLE 4B-7.  OCCUPANCY LOADS
Building Type	Conditioned Floor Area  (ft.2/person)	
Assembly	       50	
Office	     275	
Retail	     300	
Warehouse	15,000	
School	       75	
Hotel/Motel	     250	
Restaurant	     100	
Health/Institutional	     200	
Multifamily	       2 per unit	
3.1 5.1  Calculation Procedures
35.1.1  Cooling System Design Loads.  Cooling system design loads, for the purpose of sizing HVAC systems and equipment, shall be determined in accordance with one of the procedures described in Chapter 26 of the 2001 ASHRAE Handbook of Fundamentals or ACCA Manual N, Commercial Load Calculation, 4th Edition, 1988.
35.1.2  Interior Design Conditions.  Indoor design temperature and humidity conditions for general comfort applications shall be in accordance with the comfort criteria established in ANSI/ASHRAE Standard 55-92, Thermal Environmental Conditions for Human Occupancy, or Chapter 8 of the 2001 ASHRAE Handbook of Fundamentals, except that winter humidification and summer dehumidification are not required.  
35.1.3  Exterior Design Conditions.  Outdoor design conditions shall be selected from the 2001 ASHRAE Handbook of Fundamentals, or from data obtained from the National Climatic Center or a similar recognized weather data source.  Cooling design temperatures shall be no greater than the temperature listed in the 2.0% column or statistically similar 0.5% annualized value.  Heating design temperatures shall be no lower than the temperature listed in the 99% column or statistically similar 0.2% annualized value. 
Exception: Where necessary to assure the prevention of damage to the building or to material and equipment within the building, the 1% column for cooling may be used.
5.1.4  Ventilation.  Outdoor air ventilation loads shall be based on ventilation rates specified in ASHRAE Standard 62-1989.
5.1.5  Envelope.  Envelope cool loads shall be based on envelope characteristics such as thermal conductance, solar heat gain coefficient, and air leakage consistent with the values used to demonstrate compliance with FLA/COM of this Code.
5.1.6  Lighting.  Lighting loads shall be based on actual design lighting levels or power budgets consistent with the prescriptive requirements of section 415.1.  Lighting loads may be ignored for the purpose of calculating design heating loads.
5.1.7  Other Loads.  Other HVAC system loads such as those due to people and equipment shall be based on design data compiled from one or more of the following sources:  
1.  Actual information based on the intended use of the building.
2. Published data from manufacturers' technical publications.
3. Technical society publications such as the 1995 ASHRAE Handbook of HVAC                     Applications.
4. Allereza, "Estimates of recommended heat gains due to commercial appliances                    and equipment."
5. Other data based on designer's experience of loads and occupancy patterns.
Internal heat gains may be ignored for the purpose of calculating design heating loads.
5.1.8  Safety Factor.  Design loads may at the designer's option be increased by as much as 10% to account for unexpected loads or changes in space usage.
5.1.9  Pick-up Load.  Transient loads such as warm-up or cool-down loads which occur after off-hour setback or shutoff may be calculated from principles based on the heat capacity of the building and its contents, the degree of setback, and desired recovery time; or may be assumed to be up to 10% for cooling and 30% for heating of the steady-state design loads.  The steady-state load may include a safety factor in accordance with section 5.1.8 of Appendix B.
6.1  Lighting
6.1.1  Retail Establishments.  Building classifications for retail establishments have been set for the purpose of determining a lighting power allowance for buildings based upon the following primary design functions:
TYPE A--jewelry merchandising, where minute examination of displayed merchandise is critical.
TYPE B--fine merchandising: fine apparel and accessories, china, crystal and silver, art galleries, etc., where the detailed display and examination of merchandise is important.
TYPE C--mass merchandising:  general apparel, variety, stationery, books, sporting goods, hobby, cameras, gifts, luggage, etc., displayed in a warehouse type of building, where focused display and detailed examination of merchandise is important.
TYPE D--general merchandising:  general apparel, variety, stationery, books, sporting goods, hobby, cameras, gifts, luggage, etc., displayed in a department store type of building, where general display and examination of merchandise is adequate.
TYPE E--food and miscellaneous:  bakeries, hardware and housewares, grocery, appliances and furniture, etc., where appetizing appearance is important.
TYPE F--service establishments:  establishments where functional performance is important.
6.1.2   Maximum Percent Skylight Area
TABLE 4B-8 
Maximum Percent Skylight Area
For Given Conditions of Lighting Power Density and Light Level (fc), VLT = 0.75
Climate Zone	Light Level (fc) 	Range of Lighting Power Density (W/ft2)	
		<1.00	1.01-1.50	1.51-2.00	2.01-2.00	>2.50	
1,2,3		30	2.3	3.1		3.9	4.7	4.7	
4,5,6		50	3.1	4.3	5.5	6.7	6.7	
	70		4.3	5.5	6.7	7.9	7.9	
7,8,9		30	2.2	2.8	3.4		4.0	4.0	
	50		2.3	3.1	3.9	4.7	4.7	
	70	2.9	4.1	5.3		6.5	6.5	
TABLE 4B-9
Maximum Percent Skylight Area
For Given Conditions of Lighting Power Density and Light Level (fc)
VLT = 0.50
Climate Zone	Light Level (fc) 	Range of Lighting Power Density (W/ft2)	
		<1.00	1.01-1.50	1.51-2.00	2.01-2.00	>2.50	
1,2,3		30	3.6	4.8		6.0	7.2	7.2	
4,5,6		50	4.8	6.6	8.4	10.2	10.2	
	70		6.6	8.4	10.2	12.0	12.0	
7,8,9		30	3.3	4.2	5.1		6.0	6.0	
	50		3.6	4.8	6.0	7.2	7.2	
	70	4.2	6.0	7.8		9.6	9.6	
6.1.3 Unit Lighting Power Allowances
6.1.3.1  Equations
EQUATION 4-9:   INTERIOR LIGHTING POWER ALLOWANCE
ILPA = (LPB1 + LPB2 + ... + LPBn) + (0.20 W/ft2 x USA)
Where:   ILPA = interior lighting power allowance, W
  LPB = lighting power budget for each activity area, W
 USA = unlisted space area = (GLA - Sum(LS), ft2)
 GLA = gross lighted area, ft2
    LS = listed space
EQUATION 4-10:  LIGHTING POWER BUDGET
LPB 	= A x UPD x AF
Where:   LPB 	=  lighting power budget of the space, W
   A	=  area of the space, ft2
UPD 	=  unit power density, W/ft2 
 AF 	=  area factor of the room (from Equation 4-11)
EQUATION 4-11:  AREA FACTOR
AF = 0.2 + 0.8 (1/0.9n)
Where:    n = 10.21(CH - 2.5) - 1
       Ar
    	AF = area factor 
    	CH = ceiling height, ft
    	Ar = room area, ft2
EXCEPTIONS:
1. If AF < 1.0, then AF = 1.0
2. If AF > 1.8, then AF = 1.8