An unfinished basement is a blank canvas: future man cave, media room, or, possibly the perfect place for a quiet master suite away from the kids. Unfinished basements are wonderful additions, but, when it comes time to build, what happens when you discover that the concrete surface is not straight and level. Many concrete pads have high and low spots and this can be problematic when you go to put flooring down, but it’s not the end of the world, concrete slabs can be adjusted and leveled in just a few steps.
To begin remove everything from the floor of the room, including the trim, if applicable. Use a levelling bar, and drag it over the surface of the concrete floor, marking all of the high spots. You can determine high spots visually: with the levelling bar on the floor, look outward from the center and if the levelling bar appears to be at a higher angle or floats in the air then you know you have a high spot. Mark the entire high spot. With the spot marked, it is time to grind down the concrete to level with a concrete grinder. A concrete grinder is a dangerous tool if used incorrectly, so make sure that you feel comfortable with the tool and you have read and understood all of the manufacturers instructions (If you feel uncomfortable using the tool, call in a professional for help). Run the concrete grinder in small circles over the high spot to level it. When you have grinded down all of the high spots, again check the floor for level.
With a roller, spread a layer of adhesive to the concrete floor. The adhesive will help the leveling compound to adhere to the concrete. Mix the leveling compound to the standards of the manufacturers instructions—most manufacturers want the compound to have the consistency of batter. If there are any floor drains cover them with a pipe. When the adhesive is dried, although still tacky—like a glue—pour out the self levelling compound over the floor. Move it around with a squeegee. The low areas of the concrete will fill in, and the floor will come to level. After the compound has dried, usually 48 to 72 hours, you are ready to start building that perfect getaway.