Wash. Admin. Code § 51-11C-61081 - Section A108.1 - General

A108.1 General. Tables A108.1(1) and A108.1(2) list effective air change rates and heat capacities for heat loss due to infiltration for Single-Family Residential.

The estimated seasonal average infiltration rate in air changes per hour (ACH) is given for standard air-leakage control (see Section R402.4 for air leakage requirements for Single-Family Residential). The effective air change rate shall be used in calculations for compliance under either the Component Performance or Systems Analysis approaches.

Heat loss due to infiltration shall be computed using the following equation:

Qinfil

=

ACHeff * HCP

Where:

Qinfil

=

Heat loss due to air infiltration.

ACHeff

=

The effective air infiltration rate in Table A108.1(1)

HCP

=

The Heat Capacity Density Product for the appropriate elevation or climate zone as given below.

Table A108.1(1) Assumed Effective Air Changes per Hour

Air-Leakage

Air Changes per Hour

Control Package

Natural

Effective

Standard

0.35

0.35

Table A108.1(2) Default Heat Capacity/Density Product for Air

Zone

Average Elevation

Heat Capacity/Density

1

Mean Sea Level

0.0180 Btu/h . °F

2

2000

0.0168 Btu/h . °F

3

3000

0.0162 Btu/h . °F

Notes

Wash. Admin. Code § 51-11C-61081

Statutory Authority: RCW 19.27A.020, 19.27A.025 and chapters 19.27 and 34.05 RCW. 13-04-056, § 51-11C-61081, filed 2/1/13, effective 7/1/13.

State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.