I have a concrete slab in my house with black mastic attached to the subfloor from where the old parquet floors were. I had it tested and it does not contain asbestos.
My next question is, how do I get the floor prepared for my new engineered hardwood flooring that I want to glue down? I know that a moisture test will have to be done, but do I need to get it shot blasted or can I put a layer of something down (like ARDEX Feather Finish) and then if so what do I seal it with?
The previous company just scrapped off the black glue (concrete is still black) and laid down Mapei 980 and then the flooring. They started to bow up. So any suggestions would be great on how to prep it correctly.