Below Grade Walls

Manitoba Building Code – Foundation Walls

The amount of basement or crawlspace wall insulation required by the Manitoba Building Code will depend on the placement of the insulation (i.e. on the interior or exterior of the foundation).

In Manitoba, new homes must have at least:

• RSI-3.5 (R-20) or
• RSI-2.1 (R-12) on the inside wall with RSI-0.88 (R5) on the outside wall.

The less stringent requirement for exterior foundation insulation reflects that this method has potential advantages over interior insulation methods but is more costly.