Ontario Building Code

Homeowner Tools

These tools answer the questions homeowners and contractors actually ask — in plain English, backed by the 2024 Ontario Building Code.

How much insulation do I need?

Search your Ontario city and get the minimum insulation R-values for your ceiling, walls, and basement — straight from the Ontario Building Code.

Find my insulation requirements

How many windows can I have on my wall?

Enter your wall size and how far you are from the property line to find the maximum window area allowed under the Ontario Building Code.

Calculate my window limit

How big do my room windows need to be?

Find the minimum window area required for any room in your home — bedroom, living room, kitchen, and more — per Ontario Building Code.

Find my window size requirement

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Explain the rules to me

Read plain-English guides to Ontario Building Code topics: insulation zones, window glazing limits, natural light requirements, and egress windows.

Read the guides

Need the full technical details? Visit Ontario Building Code Tools for professional-grade calculators — full tables, compliance packages, and detailed calculations.