On grade concrete is tricky. The proper thing to do is to test what the concrete is emitting for moisture vapors.
Find the suitable floor underlayment that will perform to those emissions. Foam underlayment is made from resin/petroleum based products which will block moisture inherently.
Fiber/Felt Underlayment is made from recycled materials and will help the concrete breathe those vapors instead of just blocking them helping to inhibit mold and mildew situations. It manages moisture and will not allow moisture to pool under the blocker like foam. Pull back a welcome mat once on the stoop, moisture is there as the mat was blocking the emissions and allowing them to accumulate into water.
Hi! I have concrete floors in my basement. I want to place vinyl plank flooring on top of the floors. I have already applied a liquid concrete sealer, but I want to apply an underlayment that can soften that makes the plank flooring more cushioned to the feet. Do you have anything to recommend?
We would recommend QuietWalk Luxury Vinyl as it is specifically designed for luxury vinyl planks. However, if your planks are 5mm or over, it is possible to install normal QuietWalk because it is thicker and will provide more cushion.