Wash. Admin. Code § 51-11C-303135 - Table C303.1.3(5) - Small business compliance default table

Table C303.1.3(5) Small Business Compliance Table Default U-Factors for Vertical Glazing

Vertical Glazing Description

Frame Type

Any Frame

Aluminum Thermal Break2

Wood/Vinyl/

Fiberglass

Panes

Low-e1

Spacer

Fill

Double3

A

Any

Argon

0.48

0.41

0.32

B

Any

Argon

0.46

0.39

0.30

C

Any

Argon

0.44

0.37

0.28

C

High Performance

Argon

0.42

0.35

Deemed to comply5

Triple4

A

Any

Air

0.50

0.44

0.26

B

Any

Air

0.45

0.39

0.22

C

Any

Air

0.41

0.34

0.20

Any double low-e

Any

Air

0.35

0.32

0.18

1

Low-eA (emissivity) shall be 0.24 to 0.16.

Low-eB (emissivity) shall be 0.15 to 0.08.

Low-eC (emissivity) shall be 0.07 or less.

2

Aluminum Thermal Break = An aluminum thermal break framed window shall incorporate the following minimum design characteristics:

a) The thermal conductivity of the thermal break material shall be not more than 3.6 Btu-in/h/ft2/°F;

b) The thermal break material must produce a gap in the frame material of not less than 0.210 inches; and

c) All metal framing members of the products exposed to interior and exterior air shall incorporate a thermal break meeting the criteria in a) and b) above.

3

A minimum air space of 0.375 inches between panes of glass is required for double glazing.

4

A minimum air space of 0.25 inches between panes of glass is required for triple glazing.

5

Deemed to comply glazing shall not be used for performance compliance.

Notes

Wash. Admin. Code § 51-11C-303135

Statutory Authority: RCW 19.27A.020, 19.27A.025 and chapters 19.27 and 34.05 RCW. 13-04-056, § 51-11C-303135, filed 2/1/13, effective 7/1/13.

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