Save money by waterproofing your own basement walls.
Basements are subject to hydrostatic pressure, which is a cause of dampness, moisture and leaks. Hydrostatic pressure is water seepage caused by the force of the soil around your home pressing on concrete and pushing water through tiny cracks, holes and crevices in the foundation. Basement walls with larger holes and cracks provide easy entry for water leading to a wet basement. A wet basement is a breeding ground for mold and mildew and can challenge the structural integrity of a home.
Instructions
Waterproofing Paint
1. Clean the basement walls with a wire brush, power washer or sandblaster to remove paint, dirt and loose pieces of concrete.
2. Inspect the walls for mildew, mold or water stains. Scrub the stains with an equal mixture of chlorine bleach and water.
3. Press hydraulic cement into holes or cracks in the wall with a putty knife. Apply a thin layer of hydraulic cement over the crack, extending 1/2-inch beyond the crack on either side of it. Allow the hydraulic cement to dry fully, usually two to three hours.
4. Paint a coat of waterproofing masonry primer with a large paintbrush. Dab at the wall and press the brush into the surface to fill the surface crevices and cracks with primer. Allow the primer to dry for two to three hours and apply a second coat, pressing and dabbing at the wall.
5. Apply three to four thick coats of masonry waterproofing paint with a thick, fluffy paint roller. Paint the first coat in horizontal lines overlapping each other; allow the paint to dry for three to four hours. Apply the second coat in vertical lines, overlapping each other; allow the paint to dry for three to four hours. Apply the third and optional fourth coat in a V shape pattern with V's overlapping each other.
Crystalline Waterproofing Material
6. Clean the concrete walls with a wire brush, power washer or sandblaster. Remove all existing paint, dirt and debris. Scrub mold, mildew and water stains with an equal mixture of chlorine bleach and water.
7. Apply hydraulic cement to holes and large cracks with a putty knife.
8. Spray the wall with plain water. In a wheelbarrow or trough mix crystalline waterproofing material (CWM) with water to form a slurry, which means a watery paste consistency. The mixture will feel warm to the touch. This is normal.
9. Dip a large masonry paintbrush into the slurry and paint a 1/4- to 1/2-inch thick coat on the wall. Continue to wet the wall and apply a thick, uniform coating until CWM covers all walls.
10. Wet the CWM every four to six hours with a light spray of plain water to prevent it from drying. Continue to wet the CWM for 48 to 72 hours or as directed by the manufacturer. The water helps the CWM fill in the small crevices and holes creating a barrier.
Tips Warnings
When water touches CWM, crystals grow and fill in the recesses and holes in concrete. CWM never stops working and continues to seal breaks in the wall.
Wear safety glasses, gloves and a dust mask when waterproofing basement walls.