Basement subfloor options – Do it yourself in choosing and installing the basement subfloor can be a good way to save your cash with great result. We recently renovated our basement. We have done our best in upgrading the energy efficiency including the insulation upgrades. Although based on some of threads, they may have made a few not optimal decisions. We are in an historic district so we cannot make any changes to the exterior. We are now seeking to upgrade our basement floor specifically insulating it for sure.
By the previous owner, this is an existing floor poured in the early nineties. It is a 4” thick slab sitting on a sand or soil base. The ground is very sandy in our particular location. We have no leaks and it is very little moisture except for one area (6×36). It is where the below grade exterior brick is absorbing moisture right from the ground soil. Well, the plan is to dig out the exterior area and install a water vapor barrier in the spring. We want to start in insulating the floor and installing a finished floor. I have read through all of the threads on the net and believe the below is the best way but am looking for any experience.
1” XPS foam board with directly taped seams on slab. 5 plywood mounted perpendicular to the XPS and anchored to the slab through the XPS using tapcon screws. 5 plywood mounted perpendicular to and anchored to the first plywood layer. Finished floor options including floating cork floor, simple stain and seal of the plywood, tile, carpet tiles and so on. No wall to wall carpeting at all.