Best Way to Box Interior Cinder Block Foundation?
All, I have a house that was built in the 1940s with a cinder block foundation that runs up to about 10″ height in the room exterior walls. The cinder blocks extend into the room becasue the walls are on the outside of the blocks, as can be seen in the attached photo. I’d like to box/finish the cinder block. My gut says use furring strips, anchored to the cinder blocks (how?) with rigid foam between them then put some kind of poly-board (no rot, not that there is a moisture problem but this is at the beach and I’m not a fan of wood, in general, at the beach) over it. Any ideas? I probably should have built a false wall up to about three feet above the cinder block around the room so that the ledge is at 3′ high instead at the top of the cinder block at 1′ high. I might be able to do that but the outlets/wiring are in the walls, spray foam insulated and drywall installed. As an aside, the floor is concrete that I ground (asbestos tile and mastic removed) then dyed and clear coated, attempting to make it look like water. Any help is appreciated.
I did a search for finishing cinder block walls and couldn’t find anything. Sorry if I missed it.
Steve
Replies
I owned a cinderblock (CMU) house for years. It had furring strips anchored to the block and drywall attached to the strips and no vapor barrier. There were never any issues with moisture but we didnt live at the beach.
If I were in your position I would want to fur out the entire wall so that you dont have a shelf. Sound like you dont mind the shelf and just want to cover the CMU. If so I would coat the block with a liquid applied vapor barrier or just use plain Red-Guard.
If you are worried about drywall use Dense armor plus (it's a fiberglass faced gypsum board that can be submerged and dry out without any worries. Use fiber mesh instead of paper at the joints and you will be good to go.
Great advice. Thank you, Sawdust_Steve.
I'd simply cover it with tile.
Definitely one option. Since I want a little (2" foam, maybe) insulation there it will make tile more difficult. Thanks for the idea.