Finishing Basement - Insulating Walls and Floors
I am new to the forum and just scheduled my home inspection on my first house!
I have worked at Lowes for 10 years and that gives me about zero practical knowledge but 100% confidence that I can do a lot of stuff myself with the right advice and access to a lot of information.
The house I am looking at has 945 square feet of unfinished basement space. Built in 1988' it has poured concrete walls, 7' 3" of ceiling height (about 5 feet below ground), and when I move in I plan on starting the finishing project right away.
The basement has a French drain all around the perimeter and looks to be bone dry
I've been reading posts on here and other forums and I'd love to get some help/advice. Most of what I've used to formulate my plan has come from posts on this and other forums by "Dana" who seems to have a lot more technical knowledge than I can access anywhere else.
My plan was to stud directly to the concrete walls with PT 2X4 every 24" OC around the perimeter walls and then use 2" XPS adhered in between all around. I would take care to insulate near the sill plate. Then, because of ducting and headroom requirements, I was going to put 6 mil down throughout overlapped 12", 1" XPS on top of that, 1/2" plywood screwed down, and then carpet or laminate floor. Once I get my electrical in, I plan to use green board throughout on my studs.
A few questions:
1) are there any off gassing concerns using so much XPS?
2) how should I run the 6Mil to not create a problem for my French drain? I've read you should run it up the walls, but I don't know if that will cause an issue for the drain
3) does this sound like sufficient insulation for the walls/floor?
4) any mold concerns with this approach?
5) between the 2x4 and XPS, should I use spray foam to seal my seams or will Tyvek tape suffice. I have a concern about off gassing with the Great Stuff Foam in large quantities.
6)I was planning to keep a part of the basement as utility room and finish the walls but not the floors. Will this cause any moisture issues? I am planning on setting up 70 pint dehu's with humidistat set low.
Thanks in advance for any help. This is exciting and nerve racking all at the same time. The more I read the more I realize how many people make horrible mistakes with their renovation projects in their homes and mostly it's because they don't want to research or ask questions when they don't understand. Maybe THIS is what I've gotten out of working at Lowes for so long. LOL!