Converting a Garage into an Apartment
I want to convert a garage into a studio apt but the slab is 12” below the rest of the house. I want to raise the floor aprox 8-10 inches above the slab to create room for plumbing, proper fall for sewer junction and last but not least to avoid cutting through the slab. I will place a wood floor over the subfloor.
I am considering a few strategies to do this:
1) delta ms or fl moisture barrier with foamular 250 ngx then plywood then floor joists with plywood and wood flooring on top.
Is this overkill? Would I need to insulate between the joists? What thickness of insulation board would be ideal. Do I need to fasten the next to the floor? Wouldn’t that ruin the thermal and condensation barrier? Could I float it with two layers of plywood?
2) what if I simply used 2 layers of the NGX at 4” over the slab and delta ms or fl with plywood on top not fastened. Obviously taped and alternating seams? Maybe two layers of plywood?
3) could I place the delta ms or fl, sleepers and floor joists with insulation inside over that?
4) last maybe I just place the delta and some ngx and don’t raise the floor and suck it up and cut through the slab?
Lastly most cost effective method- the ngx at 4” is not cheap but compared to lumber and the ease of placement it might be worth it- not to mention the thermal value. Any suggestions here would be appreciated.
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