I have enjoyed reading the great advice on this forum for hardwood installations. My husband and I are planning our first install, most likely of engineered wood, and are trying to decide what to do to prepare our subfloor, which is a broom finished concrete slab.

Because approximately 1 gallon of peanut oil was spilled on the slab , we are not sure how clean we can get it for an application of an Ardex product to even out some small dips, or for a vapor barrier such as Bostick's MVP.

We are considering:

1) Floating subfloor of 1/2" plywood screwed and glued to 1/2" plywood as mentioned in other posts, with 6-mil poly underneath and asphalt felt on top. The only height concern we have is with the exterior door (which has not been installed yet)....the step "up" might be a little high.

2) Application of Bostick's MVP, then nailing 1/2" plywood to the concrete with a nail gun.

3) Cleaning the slab as best as we can, then gluing vinyl down, then gluing to the vinyl.

The Ardex rep we spoke to said that to use their product, we would have to clean the oil up "as deep as it penetrated into the slab," and we aren't sure how to do that, or if it is possible. We appreciate any recommendations.

try scrubbing it with Greased Lightning using a brush. that stuff is great for removing anything greasy. for the $3 bottle, it's worth the try.

just a suggestion.