ASHRAE-90.1-2022- - Page 051
Extracted Content
Table 5.5-1 Building Envelope Requirements for Climate Zone 1 (A,B)*
Nonresidential Residential Semiheated
Insulation Min. R-Value
Assembly Maximum
Roofs
Insulation Min. R-Value
Assembly Maximum
Insulation Min. R-Value
Opaque Elements
Insulation entirely
above deck
Assembly Maximum
U-0.048 R-20 c.i. U-0.039 R-25 c.i. U-0.218 R-3.8 c.i.
Metal building [ a] U-0.041 R-10 + R-19 FC U-0.041 R-10 + R-19 FC U-0.115 R-10
Attic and other U-0.027 R-38 U-0.027 R-38 U-0.081 R-13
Walls, above Grade
Mass U-0.580 NR U-0.151 [b] R-5.7 c.i. [b] U-0.580 NR
Metal building U-0.094 R-0 + R-9.8 c.i. U-0.094 R-0 + R-9.8 c.i. U-0.352 NR
Steel-framed U-0.124 R-13 U-0.124 R-13 U-0.352 NR
Wood-framed and other U-0.089 R-13 U-0.089 R-13 U-0.292 NR
Wall, below Grade
Below-grade wall C-1.140 NR C-1.140 NR C-1.140 NR
Floors
Mass U-0.322 NR U-0.322 NR U-0.322 NR
Steel joist U-0.350 NR U-0.350 NR U-0.350 NR
Wood-framed and other U-0.282 NR U-0.282 NR U-0.282 NR
Slab-on-Grade Floors
Unheated F-0.730 NR F-0.730 NR F-0.730 NR
Heated F-1.020 R-7.5 for 12 in. F-1.020 R-7.5 for 12 in. F-1.020 R-7.5 for 12 in.
Opaque Doors
Swinging U-0.370 U-0.370 U-0.700
Nonswinging U-0.310 U-0.310 U-1.450
Assembly
Max. U
Assembly
Max. U
Assembly Max. SHGC
Assembly
Min. VT/SHGC
Assembly Max. SHGC
Assembly
Min. VT/SHGC
Assembly Max. SHGC
Assembly
Min. VT/SHGC
Fenestration
Assembly
Max. U
Vertical Fenestration, 0% to 40% of Wall
Fixed 0.50 0.23 1.10 (for all
0.50 0.23 1.10 (for all
types)
1.20 NR (for all types)
NR (for all
Operable 0.62 0.21 types) 0.62 0.21 types) 1.20 types)
types)
Entrance door 0.83 0.21 0.83 0.21 1.10
Skylight, 0% to 3% of Roof
All types 0.70 0.30 NR 0.70 0.30 NR 1.80 NR NR
- The following definitions apply: c.i. = continuous insulation (see Section 3.2), FC = filled cavity (see Section A2.3.2.5), NR = no (insulation) requirement. a. When using the R-value compliance method for metal building roofs, a thermal spacer block is required (see Section A2.3.2). b. Exception to Section 5.5.3.2 applies for mass walls above grade .
ANSI/ASHRAE/IES Standard 90.1-2022 (I-P) 49