NBC 2025 update

What are the NBC 2025 requirements for alterations to existing buildings in Canada?

The NBC 2025 introduces a dedicated Part for existing buildings that clarifies how code requirements apply to alterations, including triggers for improving energy performance of HVAC systems, building envelope assemblies, fenestration, and air barrier systems in Part 9 buildings undergoing renovation.

One of the most significant additions in the NBC 2025 is a new Part specifically addressing alterations to existing buildings. Previously, applying the code to renovations was ambiguous and varied widely by jurisdiction. The new provisions clarify what triggers compliance, what level of improvement is required, and how energy performance upgrades apply to HVAC, service water heating, envelope assemblies, fenestration, doors, skylights, and air barrier systems.

What to check first

  • New dedicated Part in the NBC specifically addressing code application to existing building alterations.
  • Clarifies triggers for when energy performance improvements are required during renovation.
  • Covers HVAC, service water heating, envelope, fenestration, and air barrier upgrade requirements.

Jurisdiction notes

National baseline

The new existing buildings Part is part of the NBC 2025 model code and requires provincial adoption to take effect.

Provincial variations

Some provinces already have existing building provisions or renovation codes that may differ from or supplement the NBC 2025 approach.

Scope limitations

The initial scope focuses on energy performance upgrades in Part 9 buildings. Broader structural and life safety provisions for existing buildings may evolve in future editions.

Work through it in this order

  1. Confirm whether your province has adopted the NBC 2025 existing buildings provisions.
  2. Determine the scope and extent of the planned alteration to identify which upgrade triggers apply.
  3. Review the specific energy performance requirements for the affected building systems.
  4. Document compliance with the applicable upgrade provisions for the permit application.

Common questions

Does every renovation now require full code compliance?

No. The new provisions set specific triggers based on the scope of alteration. Minor renovations may not trigger energy upgrade requirements.

Does this apply to Part 3 buildings?

The initial scope focuses primarily on Part 9 buildings. Part 3 existing building provisions may be expanded in future code editions.

What if my province has its own renovation code?

Provincial renovation codes or existing building provisions take precedence where they differ from the NBC 2025.