A few days ago there was a topic of insulating basement walls. There
was discussion of what was best. Someone pointed out using 1" XPS foam
board directly on the concrete walls, then using R13. . So now as I am
gutting out 1 room of my basement, I have a poured concrete wall, and
i'm trying to figure out what is best.
I had old wall paneling and old insulation from when the house was
built in 1960. When I removed the paneling, it did have some mold, but
I think that this was due to the fact that the wall was 2X3 and the
insulation and studs was tight against the walls, not allowing the
walls to "breathe". The concrete walls are in good shape. No signs of
real water problems.
My plan was to use build a new 2X4 wall, but leave about an 1" or so
away from the walls to allow the walls to breath and also so the r13
insulation would not touch the walls. I was also planning on using
"Thoroseal" on the walls to seal it good. Was wondering if its better
to leave a gap behind the walls and besides losing an inch of real
estate, any downside to doing it like this? Also am I still better
using 1"XPS on the walls?