for Cold Climate Housing and much more

Last Updated: , Created: Thursday, October 14th, 1999


A basement that has more than 50 per cent of its height sticking out of the ground is not really a basement. The walls should be treated as ordinary, above-ground walls. The foundations should be treated as slab-on-grade to avoid frost problems.

Interior/exterior insulation combinations can be used to ensure that the foundations do not freeze. Insulate the inside wall to full height but add exterior insulation from grade to footing to keep the foundation wall above freezing.

This is easier to visualize if you think of your house as slab-on-grade. Exterior insulation of the full wall eliminates the complications of installing flashing for the underground insulation, as the flashing can join to the house siding.

Keywords: Crawl Space, Foundation, Walls, Frost, Basement, Freezing, Insulation, Flashings, Problems

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