RESIDENTIAL USE OF SECOND UNDERLAYMENT UNDERNEATH HARD SURFACE PRODUCTS WITH ATTACHED UNDERLAYMENT
Floating Vinyl with Attached Acoustical Underlayment
A second underlayment is allowed under any currently sold Shaw/Coretec Product with attached foam or cork underlayment in a residential application. IIC (ASTM E492-09) and STC (ASTM E90-09) lab testing on certain Shaw/Coretec products tested with and without a second layer of underlayment, to date, does not indicate that a second underlayment will significantly improve the acoustics of a floor/ceiling assembly. When used the second underlayment must be a maximum of 3 mm thick.
The additional underlayment when used must be fully adhered to the subfloor with the appropriate adhesive. The subfloor must meet all requirements of being clean, flat, dry and structurally sound prior to installation of underlayment and flooring.
Soft Step Underlayment
COREtec’s Soft Step Underlayment makes our flooring one of the quietest hard surface products on the market today. Even at these unprecedented levels, we understand that sometimes our customers want the added security of an additional underlayment.
Since its introduction, we have been testing our products on multiple additional underlayments to help meet our customers meet requirements for a second underlayment. The result of that testing has resulted in the approval of our COREtec Original with Soft Step over our Hush III and 6 mm Cork underlayments.
The additional underlayment when used must be fully adhered to the subfloor with the appropriate adhesive. The subfloor must meet all requirements of being clean, flat, dry and structurally sound prior to installation of underlayment and flooring.
Other Products
Below is a list of platforms that secondary underlayment is not approved for: