Many older homes with basements will need waterproofing at some point if not already done. Cracks can form and improper water drainage around the outside will contribute to the accumulation of water in your basement. There are some basic steps that all home owners can take to waterproof their basement and transform it into a safe and usable room in their home.
The first step in the process of basement waterproofing is to inspect the perimeter of your house. As the house settles, the soil may taper downward towards where it meets the foundation. For the best drainage, it should taper upward towards the foundation. This will force any moisture to be drawn by gravity away from the house, and away from the basement walls.
As you continue with the outside inspection, make sure that the gutters are clear and that the downspouts direct the drainage away from the house. The gutter downspouts should discharge at least 5 feet away from the base of the house or more if feasible. This will keep rainwater accumulated by the roof from saturating the soil around your foundation.
Many homes have shrubs, flowers beds, and other plants around their foundation. Rotted roots can become a conduit for water drainage from the surface and if they are too close to the foundation of the home, it can add to the amount of water leaking into your basement. Try to plant shrubs and bushes at least a foot away from your foundation and basement wall.
Although somewhat expensive, a homeowner can also dig a trench to the depth of their foundation around the perimeter of their house, and a waterproof coating can be applied to the foundation walls. Panels are then mounted on top of the coating to direct the water into a french drain system. A french drain is a perforated drain pipe buried in a bed of gravel a couple of feet below ground level and is designed to direct ground water away from the house to a storm drain or another part of the property.
There is a type of bentonite clay called hydroclay that can also be injected around a foundation. Bentonite is used as a sealant for ponds, tunnels, manholes, etc. Using hydroclay to fill voids around the foundation will act to waterproof or seal the affected area.
Once all the external or outside criteria for proper drainage are met, it is time to waterproof the inside of the basement as well. This may involve sealing cracks, applying waterproof coatings, and installing a sump pump system.
Small cracks and gaps can be filled with masonry caulk. For gaps wider than 1/8 inches, an epoxy is used. Silicon based concrete sealers can be applied to the basement wall and will penetrate into the wall surface, reacting chemically to form a hard water- proof shell that will not flake or crack. This surface can be then be painted.
There are also waterproof coatings and paint that can be used instead of the silicon based concrete sealer. These are similar to standard paint, but are applied more thickly. Waterproof paint can be applied over previously painted surfaces, but concrete waterproof coatings cannot. Check the product label to make sure. Make certain that any mineral deposits left around cracks are removed before applying any sealants, coatings, or paints. Muriatic acid can be used to dissolve and wash these deposits away.
Before undertaking any basement waterproofing project, it is a good idea to seek professional advice. Sometimes a job can be done by the homeowner. If it is more complicated, it should be contracted to someone more qualified.