Basement remodel: basic newbie questions
Hello. I am redoing a “basement” in a Californian split level out in zone 5 PA. I was hoping to ask for some advise. The basics: the “basement” is open to the upstairs. Built into a hill. Half above half below grade. The northwest-facing walls are 100% to 50% exposed with nice stone work and long horizontal windows. The southeast walls are below grade. the floor is a nice cement slab with a fairly open 1/4 inch cove joint. Radon mitigation installed. Radiant heat (water pumped) in the cement floor.
When we moved in 6 months ago it had wood paneling with horizontal furrow strips nailed into the cinderblock – touching, and fiberglass paper backed insulation directly against dryloc – like painted cinderblock. Suffice to say the entire joists and walls were mold covered and all the horizontal furrow strips were either wet or dry rot. The garage was open to the basement (via the ceiling joist – right above a furnace in a garage – so a spectacular a condensation point).
The garage joists spaced have been closed between the garage and “basement”. I’ve torn down everything to the cinderblock walls and I’ve sanded the wall, removed old fiberglass sill plate insulation.
im now in an observation phase. So far we’ve had 5 down pours. One causes flooding of a down hill creek a block away by 8 feet. The others less so. I’ve seen no water entry. I clogged the down spouts for one massive rain and saw damp cinderblock on the south west corner of the space where I clogged it. Still no water into the space itself. Cinderblock dried two days with dehumidifier on.
that back corner I plan on keeping as a unfinished 18 x 6 foot walk in storage area anyway so I will not be insulating other than the ground level rim joist areas
im thinking of Doing a mixture of insulation. There are some places because of where door frames were made originally that I cannot fit 6 inch wall. In those areas (1/2 north wall and west wall) I’d like to do 2 inches of foam core with vertical furrow strips And drywall. And other areas I’d to do what I think is recommended close cell spray foam and two by fours 1 inch off the wall.
This plan would leave half my under grade wall as breath cinderblock and the rest of the “basement” above grade as foam core or spray foam.
I have ordered and will use the rubber sill sealers below the framing floor plate treated wood since the cove joints are somewhat open.
Is this reasonable? Is this a set up for weird flash points because of three different insulation techniques?
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