We are remodeling our bathroom and are in the process of framing/insulating.
We need to insulate 2 concrete block walls but don't want to eat the already small space we have. Which solution could work?
Currently, the wall has 1×3 furring strips and we were thinking about using them to hold 2 inches insulation board—leaving some air pockets—then installing the thinner 1/4 inch Hardiebacker board and then Redgard the hell out of it for waterproofing.
My concern is the furring strips won't hold the backer board and the ceramic. Other option we thought of was using the Schluter Kerdi board and forget about insulation altogether, so Kerdi board attached to 1×3 furring and then titling.
Is there any other option that you can think of? Will any of the above ideas make sense? Thanks for asking. We are in DC (U.S.) area so summers are really hot but winters are mild.
Best Answer
I'm about 2 hours south of you. Cut 1/2" styrofoam between those strips, use a wide flashing tape to cover the furring strips and lap over onto each piece of stryofoam to the left & right of the furring strip.
Then, Keep gettin up. Put you some good 1/2" material on the wall, for the sake of your tile. I suggest cement board, but you'll do what you prefer.
The difference between what I just suggested, and 2" of foam, will make no difference in perceived heat loss, or electric bill increase.