Basement Slab Skim Coat Coming Up

Hey all, looking at a house for a friend. Seems like an extra skim coat was applied to the basement slab after construction on this 15 year old model home in the Chicago area. It’s flaking up and chipping in several areas, to where you can pick up a 10 inch section off the ground, exposing the slab below. Multiple damp foundation cracks as well.

I suspect its a bad/cheap foundation and slab pour, given its the first home built in a cookie cutter subdivision in one of the lower elevations in the county, leading excessive moisture to pass through the slab and separate the skim coat. Thoughts?

Looks like they applied some type of coating, (poured or rolled on) and was not properly prepared like installing the proper primer for the product or too much moisture in the slab and the bond failed.
Recommend a concrete field testing agency or qualified concrete contractor to evaluate the problem and recommend proper repair.
Also that meter is not adequate to test moisture in concrete accurately, but it does look like water infiltration coming from that crack in the wall. Looks like minor shrinkage crack showing signs of efflorescence.


Spot on!

Cause: No vapor barrier under the slab, thus moisture is wicking up and separating coating from slab.
Solution: Tear it all out and do it all over again, correctly…
How’s that Marcel? :wink:


Another skim coat and a for sale sign should be effective. :sunglasses:


That’s what I warned him against doing; seems convenient, until the new coating starts to fail with no good base. He’s buying the house, otherwise it’s in pretty good condition.

Thanks for the input!