Do It Yourself Basement Water Sealing
- 1). Clean the basement. Remove all stored items, sweep, and then scrub down the walls and floor with a scrub brush and water. Remove all loose debris from the surface of the walls and floor--waterproofing materials adhere best to a smooth, clean surface.
- 2). Let the basement dry out for a couple of days after cleaning it. Basements are typically humid and concrete is a porous, absorbent material. If you have fans, use them to speed the process. Opening any windows in the basement will reduce drying time as well.
- 3). Inspect the walls, floor, and the place where these meet for fine cracks. Cut the tip off a squeeze tube of urethane caulk. Squeeze the tube as you point the tip at the cracks. Position the tip over each crack, leaving a bead of caulk behind to fill them. Flatten the caulk beads down with your finger or the flat edge of a putty knife. Leave the caulk to dry for a couple of hours or the time recommended by the manufacturer.
- 4). Mix a concrete patch to fill any cracks wider than 1/4 inch. Follow the manufacturer's directions to determine the appropriate ratio of mix to water. Apply the patch to the crack with a trowel, and check to see that the crack is filled completely. Smooth it flat to the surface of the wall with the trowel and let it dry for one day.
- 5). Seal around windows with waterproof caulk. Squeeze a bead on the inside and outside of the window frames, and flatten it down with a putty knife to keep rainwater from seeping in.
- 6). Paint the walls and floor with a concrete water sealing paint. Start with the walls, then paint the floor, starting on the side opposite the door and working backward towards the exit. Use a paintbrush if the walls are rough and a paint roller if they are smooth. Paint in even strokes, and be sure to cover every concrete surface area. Let the paint dry for one or two days.