Last year I decided to let my brother-in-law finish my basement. After he finished the framing he moved away. Now I have wood framing complete and nothing else. He claimed he knew what he was doing, but after doing a lot of research I am finding that he may have been premature putting up the framing. I've decided I'm going to finish the job myself but I have a few questions.
The previous owner put in a new basement about 20 years ago with metal support framing and all. The foundation walls are block and covered with a few coats of Drylock. In the 15 years I have lived there I have never seen water.
I'm starting to think foam insulation should have been put up on the inside of the foundation walls; between the framing and foundation. I should be able to sneak the insulation in there since my brother did leave an inch of space. Should I do this? Is there any special type of insulation and/or adhesive I should use?
Am I right in thinking Foundation Wall->Foam Insulation->Gap->Framing->Sheet Rock? Should I use moisture resistant sheet rock? IS any other type of insulation necessary in there? Is plastic vapor barrier necessary?
My brother-in-law also used green treated lumber where ever the framing touches floor. Will that be sufficient against moisture?
Thanks for your help!!
Best Answer
There are no red flags that I see in your question. I don't like drylocking walls that will be covered in basements for the simple fact that if water hits concrete I would rather it go through the concrete than sit in the concrete (where if it freezes then expands will help promote larger cracks). But you have 15 years there and nothing so good for you and with that track record I wouldn't worry about it.
I would personally run roxul in joists and then down a good foot or two below grade, with no vapor barrier (you already have drylock). So what you have is insulation that does well in basements with drylock on one side and probably a decent air gap on the other and below. Would spray foam be better... maybe. It might insulate slightly better but then it is a mess if you do have a problem getting electric/plumbing out of the foam.
Moisture resistant sheet rock? It doesn't matter unless you are having a lot of water gun fights in your basement. The greenboard protects moisture from getting in the front (a little). Any long-term moisture from the rear will effect it like it would regular drywall.
Treated lumber? Perfect. He could have used treated lumber for everything but not required.
You sound like you are off to a good start. If you have more questions let us know.