We are about to begin finishing our concrete block basement and have been doing some research. I've read all the posts here that have "basement" in the title and still don't have the answers I need.
Our basement is damp and musty smelling in the summer rainy season. We have done all we can on the outside and have not seen actual water in the basement for several years. We run a dehumidifier all summer and do not have a sump pump.
1) How do we prepare the walls before framing? They are currently painted with some type of waterproof paint (probably done in the 80s) that is chalky and flaky now. Can we use Dry-Loc or similar waterproof paint over the old paint or is that a waste of time/money? I've been told we have to scrub walls with wire brush and muratic acid. Is that true?
2) I've seen conflicting information about where to put the vapor barrier. I'm leaning toward using foil backed rigid foam against the wall (foil side toward room) and then framing up against it and using fiberglass insulation between the studs. Should I use paper backed fiberglass insulation? Do I need any other vapor barrier before installing drywall?
3) What's your opinion on cutting a thin "trench" line with a saw in the cement floor along the walls and installing aluminum flashing in it to direct any water seepage to a drain or pump? Is this a crazy idea?
If anyone can answer one or all of these question, I'd really appreciate it!