RA3.8   Field Verification and Diagnostic Testing of Building Air Leakage

RA3.8.1    Purpose and Scope

The purpose of this test procedure is to measure the air leakage rate through a building enclosure or a dwelling unit enclosure.

The measurement procedure shall be based on the specifications of Residential Energy Services Network's (RESNET) Standard for Testing Airtightness of Building Enclosures, Airtightness of Heating and Cooling Air Distribution Systems, and Airflow of Mechanical Ventilation Systems (ANSI/RESNET/ICC 380-2016) (RESNET 380) as further specified in Subsections RA3.8.2, RA3.8.3, RA3.8.4 below.

This enclosure leakage procedure is applicable to:

      Single family building enclosures

      Multifamily dwelling unit enclosures

RA3.8.2    Instrument Specifications

The instrumentation for the enclosure leakage measurements shall conform to the specifications in RESNET 380 Section 3.1.

RA3.8.3    Enclosure Leakage Measurement Procedures

The enclosure leakage measurement procedure shall conform to the following specifications:

1)   The procedure for preparation of the building or dwelling unit for testing shall conform to the applicable requirements in RESNET 380 Section 3.2.

When compliance with Standards Section 150.0(o)1Eii maximum dwelling unit enclosure leakage rate is required to be verified, the test shall be conducted with the dwelling unit as if it were exposed to the outdoor air on all sides, top and bottom by opening doors and windows of adjacent dwelling units.

2)   The procedure for installation of the test apparatus, and preparations for measurement shall conform to RESNET 380 Section 3.3.

If the results of the test will be reported in cubic feet per minute at 50 Pa (0.2 inch water) (CFM50) per ft2 of dwelling unit enclosure area, the dwelling unit’s interior surface area in ft2 shall be recorded (i.e. the sum of the area of walls between dwelling units, exterior walls, ceiling, and floor).

3)   The procedure for the conduct of the enclosure leakage test shall conform to the One-Point Airtightness Test specified in RESNET 380 Section 3.4.1.

RA3.8.4    Determination of Test Results

The results of the test shall be determined as follows:

1)   The leakage airflow in CFM50 determined by the One-Point Airtightness Test specified in RESNET 380 Section 3.4.1 shall be adjusted using RESNET 380 Section 3.5.1, equation (5a).

2)   If required for compliance, the leakage results determined by RESNET 380 Section 3.5.1, equation (5a)  shall be converted to air changes per hour at 50 Pa (0.2 inch water) (ACH50) using RESNET 380 Section 3.5.2, equation (7a).

3)   If required for compliance, the leakage results determined by RESNET 380 Section 3.5.1, equation (5a) shall be converted to CFM50/ft2 of dwelling unit enclosure area by dividing CFM50 by the dwelling unit’s interior surface area in ft2 (i.e. the sum of the area of walls between dwelling units, exterior walls, ceiling, and floor).

RA3.8.5    Determining compliance

If the applicable value(s) for CFM50, ACH50, or CFM50/ft2of dwelling unit enclosure area determined in Section RA3.8.4 are less than or equal to the enclosure leakage compliance criterion specified by the Standards or the Certificate of Compliance, the enclosure complies. Otherwise the enclosure does not comply.