I bought a roll of FloorMuffler UltraSeal underlayment (essentially, sealed high-density foam) at Home Depot for this project. The instructions are very specific about which adhesive to use: "To be used with FloorMuffler HPA adhesive only".
This is problematic for at least two reasons:
- It is not clear whether the installation will fail with any other type of adhesive, or they simply prefer that I buy their product. It has become fashionable, of late, to put statements in the manuals such as "this product will only function with OEM parts", some of which are outright ridiculous, e.g. use only XYZ-brand memory sticks with your XYZ digital camera, etc. Unfortunately, in this case I cannot tell whether I can ignore it or need to take it seriously.
- Home Depot does not sell required adhesive. Worse still, I could not find it anywhere on the internet. They also have two different products, one to glue the foam to concrete, another to glue flooring to the foam. Seriously? To aggravate the problem, the manufacturer does not specify the type of glue they require, so I cannot even attempt to guess if it can be substituted or not. And by the way, the company's customer support is not returning phone calls, so no help there.
I bought some generic brand acrylic urethane glue for engineered hardwood flooring. Should I just go ahead and use that?
Update:
I glued underlayment to concrete using Roberts Engineered Wood Flooring Adhesive. The instructions say "open time up to 20 minutes" and "install hardwood while the glue is still fresh, do not allow it to skin-over". I probably gave it 10 minutes of open time before I rolled underlayment on top of freshly applied glue. There was a lot of trapped air that caused bubbles. I pierced them and pressed the air out. Next morning I was ready to install the floor, but I noticed the glue under the underlayment is still fresh. It cured around the edges, but it is completely fresh otherwise. What did I do wrong? What are my options now? I also posted this as a separate question.
Best Answer
There is no reason to glue down engineered hardwood floor to an underlayment. This is just for initial aesthetics. The glue will NEVER last (in a residential setting). The only thing the glue will do is give you fits and make your install seem tighter. Within weeks or months the glue will come loose and you will have a floating floor.
Nothing wrong with a floating floor. But the fact is you should be gluing the pieces together, not under them. The big boxes sell the generic engineered wood flooring glue. Buy that and glue your pieces together, not under them. The only time I have seen gluing to the floor to be an option is thin flooring onto concrete for commercial purposes. The only thing I would glue down in someone home is vinyl sheets/squares.