Answer
Oct 05, 2020 - 02:43 AM
You can use cork underlayment under nail down flooring, but it means for more complicated installation, as if you mechanically fasten through a sound underlayment barrier, such as cork, it severely diminishes the performance of the cork (all those nail holes will compromise the underlayment) - so yes, fasteners through the cork is bad. To properly use cork underlayment with a nail down floor, loose lay or glue down the cork underlayment to your subfloor, then place a double layer of 3/8" plywood, glued and screwed together at right angles over the cork underlayment, and then nail the wood floor to the plywood. This will keep the acoustic and insulating properties of the cork intact. This is speaking in general terms - please see the installation instructions for your flooring to see what they recommend for underlayment.If you are seeking something that can be used with nail down floor without these extra steps and layers, check out Quietwalk Plus
