Calculate an H1 R-Value solution for your concrete foundation

1. Choose your location

Click your build location on the map to select the climate zone.

Firth’s Online R-Value Calculator uses the H1 methodology, as described in the Building Code amendment H1 Energy Efficiency Acceptable Solution H1/AS1 - 5th Edition for all housing, and buildings (up to 300m2), to recommend concrete slab foundation insulation solutions using CodeMark certified Firth products and systems (only).

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2. Choose your Firth foundation system

3. Area and perimeter measurements

4. Your H1 Solution