I am excavating an unventilated foundation due to moisture problems. Floor beams and the wooden floor have rotted and been removed. The downspouts go directly into the foundation and this will be addressed and drained.
I plan to install 100mm gravel, 200mm insulation, underfloor heating, and a 100mm concrete slab. I have some questions:
Should I lay down a geotextile underneath? I have a 4-meter wide roll that is used for larger work, so the material is available.
My initial thought was to cast a base to keep the stone foundation in place. This will probably change to attaching reinforcement bars in the stones that connect to the slab's reinforcement mesh.
Any better suggestions?
Does anyone have a good suggestion for breaking the thermal bridge between the slab and the stone foundation? I can't find a sensible way to insulate between these two and would prefer them to be fixed together.
I will have an open fireplace in the room with a chimney to the ridge.
I have acquired XPS for this part and a reinforcement mesh that is in the style of 12mm rebar in 150mm squares instead of the standard mesh.
The plan is to use the heavier mesh and crack reinforcement where the fireplace will be. Should I place the heavier mesh underneath or on top?
