WAC 51-11-1310   General requirements.  The building envelope shall comply with Sections 1311 through 1314.


1310.1 Conditioned Spaces: The building envelope for conditioned spaces shall also comply with one of the following paths:


     a. Prescriptive Building Envelope Option Sections 1320 through 1323.

     b. Component Performance Building Envelope Option Sections 1330 through 1334.

     c. Systems Analysis. See Section 1141.4.


1310.2 Semi-Heated Spaces: All spaces shall be considered conditioned spaces, and shall comply with the requirements in Section 1310.1 unless they meet the following criteria for semi-heated spaces. The installed heating equipment output, in Climate Zone 1, shall be 3 Btu/(h • ft2) or greater but not greater than 8 Btu/(h • ft2) and in Climate Zone 2, shall be 5 Btu/(h • ft2) or greater but not greater than 12 Btu/(h • ft2).

     For semi-heated spaces, the building envelope shall comply with the same requirements as that for conditioned spaces in Section 1310.1.


EXCEPTION: For semi-heated spaces heated by other fuels only, wall insulation is not required for those walls that separate semi-heated spaces (see definition in Section 201.1) from the exterior provided that the space is heated solely by a heating system controlled by a thermostat with a maximum setpoint capacity of 45°F, mounted no lower than the heating unit.
Figure 13A

Building Envelope Compliance Options



Section

Number



Subject

Prescriptive

Option		 Component

Performance

Option		 Systems

Analysis

Option
1310

1311

1312

1313

1314		 General Requirements

Insulation

Glazing and Doors

Moisture Control

Air Leakage		 X

X

X

X

X		 X

X

X

X

X		 X

X

X

X

X
1320



1321

1322

1323		 Prescriptive Building

Envelope Option

General

Opaque Envelope

Glazing

X

X

X

X











1330





1331

1332

1333

1334		 Component

Performance Building

Envelope Option

General

Component U-Factors

UA Calculations

Solar Heat Gain

Coefficient











X

X

X

X



X







RS-29 Systems Analysis     X




[Statutory Authority: RCW 19.27A.022, 19.27A.025, 19.27A.045, and chapters 19.27 and 34.05 RCW. 07-01-089, § 51-11-1310, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27A.025. 93-21-052, § 51-11-1310, filed 10/18/93, effective 4/1/94.]