Nail Down Secret nails are used with a wood flooring nailer and mallet to attach the flooring to the subfloor. Glue Down Engineered wood floors and parquets can be glued down. This is when you spread the recommended glue all over the subfloor and lay the flooring into the glue. Floating This is when a thin underlay is placed between the wood flooring and the subfloor. A recommended wood glue is then applied into the 'tongue & groove' of each of the planks and the timbers are fitted together. (Edited, if you would like to advertise then contact ADMIN or MATT )