Flooring above garage slab
I am working on a property that is basically a 25'x30' garage on a slab foundation that has been "finished" rather poorly into a living space.
The floors were uneven, so I ripped up the tile and unscrewed a layer of 3/4" t&g to find PT 2x4s on their sides secured to the slab foundation holding up the sub floor. No vapor barrier or insulation of any kind.
The floor can likely be leveled with some shims on the 2x4s, but should I be adding a vapor barrier before I attached the 3/4" subfloor again?