Ontario Building Code (SB-12) sets minimum insulation values based on your city's climate zone. Answer two questions below to get your requirements.
Step 1 — What are you building?
Step 2 — Where is your property?
Ontario Building Code insulation requirements for residential buildings are governed by SB-12 (Supplementary Standard SB-12). The minimum R-values depend on your city's heating degree days (HDD18), placing you in either SB-12 Zone 1 (HDD18 < 5,000) or SB-12 Zone 2 (HDD18 ≥ 5,000).
Zone 1 cities include Toronto, Hamilton, London, and Windsor. Zone 2 includes Ottawa, Sudbury, Thunder Bay, and most of northern Ontario.
The values shown are minimum code requirements. Many energy programs (EnerGuide, Net Zero) require higher values. "ci" means continuous insulation — rigid foam board applied with no thermal bridging through studs.
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