Ontario Building Code Tools
Find your project's climate zone and required thermal performance using the 2024 Ontario Building Code.
Step 1 — Search your city
Type any Ontario city or location. Climate data, zone classifications, and thermal requirements will update automatically below.
↓ Climate data cards update below · Scroll down for thermal compliance tables (SB-12 / SB-10)
Step 2 — Climate data results
SB-12 Rules
• Zone 1: HDD18 < 5 000
• Zone 2: HDD18 ≥ 5 000
SB-10 Rules
• Zone 5: HDD18 < 4 000
• Zone 6: 4 000 ≤ HDD18 < 5 000
• Zone 7: HDD18 ≥ 5 000
Result for Ailsa Craig
HDD18 = 3840
SB-12 → Zone 1
SB-10 → Zone 5
Step 3 — Select your building type
Choose the classification that matches your project. The thermal compliance table below will update accordingly.
Construction
SB-12 Table 3.1.1.11
Zone: Zone 1 (HDD18 = 3840) → Zone 1 (< 5 000 HDD18)
| Component | Min. Nominal R | Max. U (Btu/(h·ft²·°F)) | Min. Effective R | ER |
|---|---|---|---|---|
| Ceiling with Attic Space | 60 | 0.017 | 59.22 | — |
| Ceiling Without Attic Space | 31 | 0.036 | 27.65 | — |
| Exposed Floor | 31 | 0.034 | 29.80 | — |
| Walls Above Grade | 19 + 5 ci | 0.049 | 20.32 | — |
| Basement Walls | 20 ci | 0.047 | 21.12 | — |
| Heated Slab / Slab ≤ 600 mm Below Grade | 10 | 0.090 | 11.13 | — |
| Edge of Below-Grade Slab ≤ 600 mm | 10 | — | — | — |
| Windows & Sliding Glass Doors | — | 0.28 | — | 25 |
• Basement Walls: Alt.: R12 + 10 ci ↔ R20 ci; or R15 ci ↔ R12 + 5 ci.
Nominal/Effective R in (h·ft²·°F)/Btu · U in Btu/(h·ft²·°F)
Source: 2024 Ontario Building Code — SB-1 (Tables 2 & 3) · SB-12 Tables 3.1.1.2, 3.1.1.3, 3.1.1.11 · SB-10 Div.3 Tables SB 5.5-5/6/7 · SB-10 Div.5 Table 1.1.1.2
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