Determination of the airtightness of building envelopes by the fan depressurization method

Note: The standard development activity for this NOI (originally published on July 25, 2023) was updated by the responsible SDO on January 9, 2024.

1 Scope and field of application

1.1 Scope

This is a standard method of tests (SMOTs) for the determination of the airtightness of building envelopes. This Standard contains three test options, two types of assessments and, for attached zones, two pressure boundary setups.

The test options are the multi-point test, the two-point test and the single-point test. The types of assessments are as-operated and closed-up. The pressure boundary set-ups are guarded and unguarded.

Each test can be used to determine the airtightness characteristics including combined area of leaks in the building envelope. It is the responsibility of the user, specifically the referencing code, standard or program, to specify what test and results are required.

These tests are not intended for determining the actual air leakage that occurs through a building envelope under the natural influences of wind and buoyancy pressures, or as a result of pressures produced by the operation of mechanical systems.