I have a 6' wide wrap-around porch. The side walls of the porch are brick and abut the brick foundation of the house (which is bricked up to the porch floor level). The wall around the porch perimeter is about 5 feet high on the back side due to the slopping grade of the adjacent lawn and only a foot or so on the front side some 16 feet forward. The porch floor is tile. Apparently when the porch was first built its perimeter was bricked properly on footers and has not settled. However the space between the brick wall of the house and the brick porch perimeter wall was back filled with dirt and not properly graveled and tamped. The cement "subfloor" beneath the tile, which is now very crumbly, was applied directly over the dirt. The house is 26 years old and the fill-dirt has settled several inches on this back side (less as you move toward the front-side of the porch where there is less fill beneath). The outside row of tile directly above the porch foundation wall is still at its proper level but the surrounding tile has settled an inch of more. I hope what I have described here makes some sense. I am looking for a solution. One obvious approach would be to remove the tile and old cement, then gravel and tamp before pouring a new cement porch subfloor but I am concerned that too much tamping could cause the porch wall to bow and that too little will result in the same settling problem in the future. Is there some suitable "bridge" material that I could put between the brick house foundation wall and the porch wall that would prevent future settling of the subfloor? Or is there some more obvious solution that I am not seeing. Your suggestions would be most appreciated.
Thanks much.