Plywood is often used as a sub-flooring. It can be installed on top of concrete before hardwood flooring or another type of material is installed. One way to attach plywood to a concrete surface is to screw it into place with concrete fasteners. Another way that involves less strain and hard work is to glue the plywood to the concrete. This only requires a few materials and will adhere the plywood very securely in place.
Brush the entire surface of the concrete off with a broom and dust pan. Run the broom over the entire surface and sweep away any dirt and other smaller pieces of debris that might be in the way. Brush them into the dust pan and throw all particles away.
Wipe the entire surface down with a clean rag. Dampen the rag with water and scrub thoroughly over the concrete surface so it is clean and easy for the plywood to adhere to.
Lay the plywood down on a flat surface, with the side that is going to be glued to the concrete facing up. Open a bucket of concrete urethane adhesive and mix it up with a trowel.
Dip the trowel into the adhesive and spread the adhesive out over the entire surface of the plywood with the trowel. Cover the whole side of the plywood with a layer of adhesive, making it about 1/8-inch thick. Spread it out evenly until the entire surface is covered. Cover the concrete in the same manner.
Pick up the plywood and set it directly on the concrete at the desired location. Run your hands over the surface of the plywood and push down firmly to secure it in place. Tap down on the plywood with a cement block to ensure all air bubbles are expelled. Repeat the process for all of the other pieces of plywood that need to adhere to the concrete.