Where to Insulate in Basement?

For interior foundation insulation, the safest choices include rigid foam board and spray polyurethane foam. Basement wall insulation can be placed on the exterior side of the wall, on the interior side of the wall, or on both sides of the wall.

Should you insulate basement walls below grade?

Your best bang for the dollar in this instance is to insulate the coldest part of the wall, again typically to 2-feet below grade. However, there are many instances where insulating the full wall is the best option, such as if your walls are stone, or the floor is earth or crushed stone with no vapor barrier.

Should basement walls be insulated to the floor?

If a basement is being used for storage or as living space, it needs to be kept dry to avoid mold and dust mites. The most important strategies for keeping basements dry are those of groundwater and rainwater control. ... Basements should be insulated on their perimeters—they should not be insulated between floors.