Hello!
We have bought a townhouse, built in '82 with pressure-treated sill plates in the exterior wall. The slab is on grade. Underfloor: Plastic sheeting, 70mm foam insulation, paper, and 22mm chipboard. Everything is now torn out, and I would like help assessing the concrete slab. Here's the situation: when everything was removed, I thought the slab looked fine. No microbial growth. What puzzles me is that there seem to be small channels on the concrete, and the concrete has crumbled in certain areas (where the concrete is lighter). My theory is that these areas have been walked on more. Now that I've torn everything out and removed the plastic sheeting, I notice a significant difference in smell. Now it smells like wet stone mixed with chlorine, similar to a swimming pool. Is this common for concrete? Do you think the concrete looks okay? In the fourth picture, there is a white coating that feels like putty or possibly an old primer, is that what it is?
Grateful for responses!
We have bought a townhouse, built in '82 with pressure-treated sill plates in the exterior wall. The slab is on grade. Underfloor: Plastic sheeting, 70mm foam insulation, paper, and 22mm chipboard. Everything is now torn out, and I would like help assessing the concrete slab. Here's the situation: when everything was removed, I thought the slab looked fine. No microbial growth. What puzzles me is that there seem to be small channels on the concrete, and the concrete has crumbled in certain areas (where the concrete is lighter). My theory is that these areas have been walked on more. Now that I've torn everything out and removed the plastic sheeting, I notice a significant difference in smell. Now it smells like wet stone mixed with chlorine, similar to a swimming pool. Is this common for concrete? Do you think the concrete looks okay? In the fourth picture, there is a white coating that feels like putty or possibly an old primer, is that what it is?
Grateful for responses!
Was there plastic wrap, 70 mm styrofoam, paper, and chipboard on top of the concrete? Is there any insulation under the concrete?
If I had to guess without knowing the construction solution, I believe the following:
they are a classic slab on grade without underlying insulation = risk construction
moisture seeps into the slab and causes damage to the overlying structure.
Moisture and odor will remain in the slab, but the solution is, as you have done, to remove the old floor and install a ventilated floor that prevents moisture/odor from rising into the home.
they are a classic slab on grade without underlying insulation = risk construction
moisture seeps into the slab and causes damage to the overlying structure.
Moisture and odor will remain in the slab, but the solution is, as you have done, to remove the old floor and install a ventilated floor that prevents moisture/odor from rising into the home.