NBC 2025 building code question

What are the NBC 2025 requirements for 12-storey mass timber buildings in Canada?

The NBC 2025 introduces provisions allowing mass timber construction up to 12 storeys under specific conditions. Encapsulated mass timber construction (EMTC) requirements, fire safety provisions, and structural performance criteria define the compliance path for tall timber buildings.

The NBC 2025 represents a major expansion of mass timber construction permissions in Canada. By enabling timber buildings up to 12 storeys, the code opens new design possibilities while imposing strict encapsulation, fire resistance, and structural performance requirements to ensure safety at height.

What to check first

  • The NBC 2025 permits mass timber construction up to 12 storeys under encapsulated mass timber construction (EMTC) provisions.
  • EMTC requires that structural timber elements be protected by non-combustible encapsulation to prevent fire exposure to the wood.
  • Fire safety requirements include specific fire-resistance ratings, sprinkler mandates, and fire department access provisions for tall timber buildings.

Jurisdiction notes

NBC 2025 national provisions

The national code introduces construction types for EMTC up to 12 storeys with specific encapsulation, fire resistance, and compartmentation requirements.

Provincial adoption timeline

Each province must adopt the NBC 2025 provisions before they are enforceable locally. Adoption timelines vary — some provinces adopt quickly while others may take years.

BC precedent

British Columbia permitted tall timber construction before the NBC 2025 through its own code provisions. The NBC 2025 aligns national requirements with BC's experience.

Work through it in this order

  1. Confirm whether your province has adopted the NBC 2025 mass timber provisions or has equivalent provisions in force.
  2. Determine the applicable construction type and height limit for your project's occupancy and building area.
  3. Design structural timber elements to meet EMTC encapsulation requirements including non-combustible protection layers.
  4. Address fire safety requirements including sprinkler systems, fire-resistance ratings, and fire department access.
  5. Coordinate with the authority having jurisdiction early, as tall timber projects may receive enhanced scrutiny.

Common questions

Can I build a 12-storey wood building anywhere in Canada?

Only where the applicable province has adopted the NBC 2025 mass timber provisions or has equivalent provisions. Check your provincial code status before designing to these height limits.

What is encapsulated mass timber construction?

EMTC requires structural timber elements to be encapsulated by non-combustible materials so the wood is not directly exposed to fire. This is distinct from exposed mass timber, which has different height limits.

Do tall timber buildings need sprinklers?

Yes, sprinkler systems are mandatory for tall mass timber buildings under the NBC 2025 provisions.