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Morton
12-16-2015, 11:27 AM
We have plans to finish our basement and have a few questions on the best way to proceed.

The basement walls are poured concrete with a concrete floor.

Should I insulate the walls?

Can the walls be covered with furring strips or should I use a two-by-four wall stud?

home improvement guy
12-16-2015, 12:14 PM
A poured basement wall, or for that fact a concrete block wall, has to dry out over time. The portion of the wall that is below the outside grade can only dry to the inside of the home. This could be several years depending on the amount of water used in construction and the air conditioning system in the home. The air conditioner removes moisture from the air and helps to dry the concrete floors and walls.

If you decide to insulate the wall, you should only insulate the portion of the wall that is above the outside grade. If you use furring strips, they must be made of treated lumber when in contact with concrete or concrete blocks. Pine, fir and other species of lumbers would rot and decay over time when in contact with the walls.

I'm not a big fan of furring strips because they have a tendency to split when fastened to the walls. I would prefer to use a standard two-by-four stud set on a treated two-by-four bottom plate and set approximately a half-inch from the existing concrete wall. This will leave an air gap, which allows the concrete wall to dry. To avoid pest and debris collection, use a strip of rigid foam attached to the top plate of the wall and sealed tightly up against the concrete wall. Because this is not a bearing wall, you can set the two-by-fours every 24 inches apart. Make sure the wall is straight and level and secure the new wall to the concrete floor and the floor studs above.