ASHRAE-90.1-2022- - Page 058

Extracted Content

Table 5.5-8 Building Envelope Requirements for Climate Zone 8*

Nonresidential Residential Semiheated

Insulation Min. R-Value

Assembly Maximum

Insulation Min. R-Value

Assembly Maximum

Insulation Min. R-Value

Opaque Elements

Roofs

Insulation entirely

above deck

Assembly Maximum

U-0.028 R-35 c.i. U-0.028 R-35 c.i. U-0.039 R-25 c.i.

Metal building [ a] U-0.026 R-25 + R-11+R-11 Ls U-0.026 R-25 + R-11+R-11 Ls U-0.037 R-19+R-11 Ls or

R-25 + R-8 Ls

Attic and other U-0.017 R-60 U-0.017 R-60 U-0.027 R-38

Walls, above Grade

Mass U-0.048 R-19 c.i. U-0.048 R-19 c.i. U-0.104 R-9.5 c.i.

Metal building U-0.039 R-0 + R-25 c.i. U-0.039 R-0 + R-25 c.i. U-0.060 R-0 + R-15.8 c.i.

Steel-framed U-0.037 R-13 + R-18.8 c.i. U-0.037 R-13 + R-18.8 c.i. U-0.064 R-13 + R-7.5 c.i.

Wood-framed and other U-0.032 R-13 + R-18.8 c.i. U-0.032 R-13 + R-18.8 c.i. U-0.051 R-13 + R-7.5 c.i.

Wall, below Grade

Below-grade wall C-0.063 R-15 c.i. C-0.063 R-15 c.i. C-0.119 R-7.5 c.i.

Floors

Mass U-0.038 R-23 c.i. U-0.038 R-23 c.i. U-0.064 R-12.5 c.i.

Steel joist U-0.032 R-38 U-0.032 R-38 U-0.052 R-19

Wood-framed and other U-0.027 R-38 U-0.027 R-38 U-0.033 R-30

Slab-on-Grade Floors

Unheated F-0.434 R-20 for 48 in. F-0.424 R-25 for 48 in. F-0.540 R-10 for 24 in.

Heated F-0.671 R-25 for 48 in. F-0.373 R-20 full slab F-0.860 R-15 for 24 in.

Opaque Doors

Swinging U-0.370 U-0.370 U-0.370

Nonswinging U-0.310 U-0.310 U-0.310

Assembly

Max. U

Assembly

Max. U

Assembly

Min. VT/SHGC

Assembly Max. SHGC

Assembly

Min. VT/SHGC

Assembly Max. SHGC

Assembly

Min. VT/SHGC

Assembly

Max. SHGC

Fenestration

Assembly

Max. U

Vertical Fenestration, 0% to 40% of Wall

Fixed 0.26 0.40 1.10 (for all

0.26 0.40 1.10 (for all

types)

0.36 NR (for all

types)

NR (for all

Operable 0.32 0.36 types) 0.32 0.36 types) 0.44 types) types)

types)

Entrance door 0.63 0.36 0.63 0.36 0.63

Skylight, 0% to 3% of Roof

All types 0.41 NR NR 0.41 NR NR 0.75 NR NR

  • The following definitions apply: c.i. = continuous insulation (see Section 3.2), FC = filled cavity (see Section A2.3.2.5), Ls = liner system (see Section A2.3.2.4); 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).

56 ANSI/ASHRAE/IES Standard 90.1-2022 (I-P)