Blower door testing for new buildings

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Blower door testing is used to measure how airtight a building is, which helps verify energy performance and identify air leakage before construction is completed. Conducting this test before drywall is installed can allow issues to be identified and corrected early, supporting energy conservation and greenhouse gas reduction objectives. In BC, local governments can likely require pre‑drywall blower door testing as an administrative requirement through bylaw, provided the requirement is carefully framed and does not conflict with provincial building regulations.

Regulatory pathways

Require blower door tests through the Community Charter

Last update: Jun. 2026

A municipality can likely require builders or developers to undertake a pre‑drywall blower door test through a bylaw enacted under section 8(3)(l) of the Community Charter. This authority allows councils to regulate and impose requirements relating to buildings, including administrative requirements that support compliance with energy performance standards.

Note: This authority applies only to municipalities; regional districts do not have a corresponding power to require blower door testing by bylaw.

How it works

  • Section 8(3)(l) of the Community Charter allows a council to regulate, prohibit, and impose requirements in relation to buildings and other structures.
  • This authority has been interpreted broadly by the courts and applies to both new and existing buildings.
  • Section 5 of the Building Act restricts local building requirements where the matter is already subject to a building regulation or prescribed as a restricted matter.
  • Blower door testing appears to be part of the Energy Step Code for certain buildings, but energy conservation and GHG reduction are classified as “unrestricted matters” under the Building Act General Regulation.
  • Local authority over unrestricted matters is subject to two conditions:
    • requirements must not require construction except in conformance with a Step Code level; and
    • requirements must not modify or impose requirements in addition to those in the Step Code.
  • A pre‑drywall blower door test does not require a different construction standard and does not modify Step Code requirements.
  • Provincial guidance indicates that section 5 of the Building Act does not prevent local governments from establishing administrative requirements to regulate or enforce building construction (for example, post‑construction testing requirements).
  • Blower door testing is comparable to these types of administrative requirements, as it supports the enforcement of energy performance standards.
  • As a result, a requirement for pre‑drywall blower door testing would likely constitute an unrestricted matter and an administrative requirement.
  • A municipality could therefore likely enact a bylaw requiring such testing, provided the bylaw is reasonable and does not regulate building construction itself.
  • Reasonableness would likely require consultation with affected builders, developers, and industry, supported by staff or expert evidence demonstrating the bylaw relates clearly to buildings.

Glossary Entry

Bylaws Under the Community Charter

The Community Charter gives municipalities the authority to regulate specific local matters by bylaw.

Part 2 of the Community Charter outlines the powers municipalities have to pass bylaws in defined areas, following a “spheres of jurisdiction” model. This means local governments can regulate, require, or prohibit certain activities—such as animal control or public health—within specific policy areas, or “spheres.”

Some of these areas are classified as spheres of concurrent authority under Section 9 of the Charter. This includes:

  • Section 8(3)(i) – public health
  • Section 8(3)(j) – protection of the natural environment

In these cases, municipalities must receive approval from the relevant provincial minister before adopting a bylaw—even if the bylaw also addresses issues in non-concurrent areas.

Glossary Entry

Blower door testing for new buildings

Blower door testing is used to measure how airtight a building is, which helps verify energy performance and identify air leakage before construction is completed. Conducting this test before drywall is installed can allow issues to be identified and corrected early, supporting energy conservation and greenhouse gas reduction objectives. In BC, local governments can likely require pre‑drywall blower door testing as an administrative requirement through bylaw, provided the requirement is carefully framed and does not conflict with provincial building regulations.