A Polymer Adhesive is used to stick Solid/Engineered floors directly to the sub floor. Whether your floor is a regular solid board or a herringbone floor, a polymer adhesive will do the job. It is a flexible adhesive which means even after adhering it to concrete, your floor still has the ability to expand naturally. This product is not suited for laminate floors. Your floor must be level before use.
Benefits of Gluing Floors Down:
When gluing down an engineered floor instead of floating it you will get major benefits. Because the entire floor will be stuck to your sub floor you will restrict movement. A polymer adhesive is a flexible adhesive so restricting movement will still allow for expansion in your floor. This means your floor will be able to move when needed but wont cause you any issues with your floor cupping. When you float the floor over an underlay there is no solid hold to your floor. This may cause your floor to expand more than if it is glued down. Gluing your floor down will also give you a much more solid feel under your foot than floating. As there is not as much movement in the floor, you will definitely have a more solid feel.
As a solid floor usually cannot be floated, the only other option is nailing it to batons. Gluing your floor down is usually the easier and better approach because if you are nailing your floor, you must allow an increase in height for the batons. This can be problematic for people whose houses are already built or in the future it completely restricts your choice if you want to change.