Encyclopedia

of Home Improvements

*Basement Leaks*

The first place to start when trying to tackle a basement water problem is your home's gutter system. Unless it is properly channeled away from your home's foundation, all that water collected by the roof can quickly saturate the ground surrounding the basement walls. This is a recipe for a wet basement, regardless of any attempts you may make to seal it from the inside. (photo 1)

Stopped up gutters create problems by forcing water to run over their sides and down to the ground, possibly damaging eaves and fascia boards in the process. Gutters should be cleaned on a regular basis.

Basement waterproofing should begin outside your home Look for areas that contribute to the collection of water next to your foundation. If you have any low spots build up the soil so that it has a pitch going away from the house. Water should be pitched away from the house. Look for areas that contribute to the collection of water next to your foundation. Fill low areas so water flows away from your foundation

New foundations are routinely waterproofed with a rubberized sealant. This Is however a very expensive project for an older house. All other alternatives should be exhausted before going this route.(photo3)

If you have cracks in your basement that allow water to leak through, you can cure the problem by using a cement crack sealer that comes in a tube or if the crack is too large, hydraulic cement will be required. It dries very quickly, even under water, and can be used to patch cracks in masonry and cement to effectively seal out water. If any water freezes in these cracks it will expand with tremendous force and only cause further damage. It is prudent to repair these problems as soon as possible.

Cement crack filler is applied with a caulking gun. Make sure the surface is clean, squeeze in the filler and wipe off any excess. (photo4)

Hydraulic cement is used to fill larger cracks. Use a cold chisel and heavy hammer to open up the crack. Try to make the inside of the crack wider than the outside so you can pack the cement into the wall. Clean off the surface being patched. Read and follow the instructions on the package for mixing. Fill the crack 1" below the surface and let the cement dry. Apply a second coat to smooth the surface. Hydraulic cement expands as it cures making a really tight waterproof patch. (photo2)

Concrete shrinks as a natural process of it curing. This shrinkage causes the concrete to develop stresses and to relieve it, the basement wall cracks. This is a normal condition in a concrete foundation. Shrinkage cracks are typically less than 1/16th" in width and will eventually run the entire length of the concrete wall, from top to bottom. Common areas for a shrinkage concrete crack to develop are under a basement window, in the middle of a long wall or where the foundation "steps down."
Once the concrete cracks it is possible for water to leak into a basement through the crack. There are several ways to repair a basement crack leak. The most effective is to perform an injection of polyurethane foam into the basement crack.
Polyurethane foams are injected into the basement crack in a liquid form. This allows a gentle and slow filling process of the basement crack that will completely fill the crack. After a few minutes the polyurethane will begin to react with the water in the crack to begin foaming. Water is actually the catalyst that converts the liquid polyurethane into foam. This foaming action increases the volume of the polyurethane up to 30x its liquid form.
As the polyurethane foam expands it fills the basement crack from bottom to top and front to back. The finished foam will be a closed cell structure that will not allow water to leak into the basement crack. In fact, if there are any voids in the soil outside of the basement- such as under a rock or if the foundation is backfilled with gravel-the polyurethane foam will expand and extend out into the void.
The polyurethane foam forms a strong bond to the concrete. This bond will be able to withstand the hydrostatic pressure that may develop from high ground water levels. High ground water levels are typically caused by heavy rains.
Basement crack injection is a quick repair process that stops water leaks. The technician does not have to drill into the concrete to do it. For this reason the basement crack repair is a clean process. The technician will attach ports to the surface of the basement crack that allow the liquid polyurethane to enter the basement wall and stop the leak.
Once the basement wall crack is completed, water will not be able to leak into the basement. Now the homeowner's possessions will be safe. As will any insulation on the basement

Sealing your basement walls and floor

After all the repairs are done and you are confident the basement is dry it is a good idea to seal out the rest of the moisture that is slowly seeping in through the pores of the concrete. There are several good quality waterproofing "paints" on the market. Your local home center or hardware store should be able to direct you as to which one suits your needs best.

The walls and floors must be cleaned of all dirt, dust, etc. before painting in order for the waterproofing to adhere properly. Many of these sealers have very strong oders, especially the oil based products. Be sure that the basement is properly ventilated before applying. If you wish, you can paint over the sealer with a color paint of your choice.

After the walls are completely dry you can start on the floor. There are many products available for your floor. I would start with 2 to 3 coats of a polyurethane sealer. Read the instructions for drying times between coats. You can also put a finish coat on by using a concrete floor paint, the color of your choice.

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