By:
What You'll Need
Dec 08, 2015 When your basement is unfinished and there is water on the floor and no evidence of a leaking foundation crack or anything else in the foundation wall, what should you think? In fact, many homeowners report that they observed that water comes up through the basement floor, usually where the wall meets the floor. Leaks in the basement floors are a common problem in homes. Whether the basement is finished or not, leaks in the floor can cause serious damage that can be costly if not repaired promptly. Not only can moisture from these leaks ruin carpets and wallboards, but it can also promote the growth of mold and fungus under the carpet and inside walls.
Hammer
Hydraulic cement
Sealant
Mortar trowel
What You'll Need
Hammer
Hydraulic cement
Sealant
Mortar trowel
Whether you use your basement as an extra room or just for storage, a basement wall leak is bad news. Not only will the dampness damage your possessions, but it can also cause a health hazard. Fixing the leak as soon as possible makes the job easier and less expensive in the long run. Follow the steps below to fix a basement leak.
Step 1 - Locate the Leak
The source of a leak is not necessarily in the same place that you found water. Trace the water to its source on the wall. Be thorough, as there may be more than a single entry point.
Step 2 - Inspect Crack
Use the hammer and chisel to carefully open cracks and voids. Inspect them for extensive damage or holes. Remember that the cracks which are visible on your wall are not the total extent of the damage. If you simply cover it, the water will find another place to go and you'll have more work to do in the future.
Step 3 - Clear Debris
Use a small brush to remove loose debris in the crack. Once you've got rid of as much as possible, use the can of compressed air for a final tidy-up.
Step 4 - Apply Hydraulic Cement
Wear protective gear. Mix hydraulic cement per the instructions on the packet. Apply the mixed cement to the crack, pressing it in as far as possible. You can also use small pieces of stone or already hardened cement to fill the gap. Ensure that they don't protrude from the wall.
For the best results, use the hydraulic cement within 10 to 15 minutes of mixing it. You must work quickly and thoroughly. To obtain a flatter finish to the wall, use a mortar trowel to apply the cement. Leave the cement to cure.
Step 5 - Waterproof Walls
Once you have filled the crack in the walls, apply a waterproof sealant to protect against future damage. These sealants should be applied to a wet or damp wall. They must dry completely before you apply a second coat.
Step 6 - Prevent Future Leaks
Now that you've repaired and waterproofed your basement, make sure it stays in the best possible condition. Check around the outside of your home for improperly connected gutters. Verify that drainage run-offs are not accumulating against the side of the house.
If you have a concrete slab or driveway next to your home, make sure that they are sloped away from the house. It is recommended to have a 1-inch slope for every 10-feet of the concrete slab.
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If a basement leak does occur, try to seal it at the source. Use caulking compound to close seams around basement windows and door frames, where pipes, cables or vents pass through the wall and where sidewalks, steps or porches meet foundation masonry.
If water seeps from cracks or holes in masonry, those openings can be plugged with hydraulic cement. Such cement, made by companies like Bondex, Quikrete and United Gilsonite, hardens in minutes, and because it expands as it sets, it bonds tightly with existing concrete.
To apply hydraulic cement, scrub all loose material from the hole or crack with a wire brush. If practical, enlarge cracks slightly with a hammer and cold chisel or a masonry chisel. so that the gap is wider toward the inside of the masonry than at the surface.
Don rubber gloves, because the cement is mildly caustic. Mix the powdered cement with cold water until the mixture is the consistency of soft modeling clay. Do not overmix, or the cement may harden prematurely.
If the opening is a hole, use your hands to form the cement into a cone about four inches long, with the base about an inch wider than the hole. Wait two or three minutes or until the cone begins to feel warm, a sign of hardening.
Next, force the cone point-first into the hole and press against it for three to five minutes, until it hardens further. Trim the edges or smooth the surface, if desired, using a mason's trowel or a putty knife.
To seal a crack, apply cement, also at the warm stage, by using a trowel or putty knife. Press the tool repeatedly over the seam until the cement hardens.
Fill deep cracks and holes just to within a half-inch of their surfaces. After the cement hardens, fill the cracks and holes completely with a second layer. If no water is flowing from a break being repaired, dampen the area thoroughly with a sponge just before applying the cement.
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Water seeping through the seam where basement walls meet the floor presents a different problem. Because the floor often settles slightly, particularly when the soil beneath it becomes saturated in spring, a more-elastic filler is needed. The best is epoxy waterproofing compound.
To apply the compound, mix it according to the manufacturer's instructions. Generally, it is a two-part product containing resins plus a hardening agent. Using a wire brush, scrub loose debris away from the seam. Then ladle or pour the epoxy into the crack.
As the material hardens, smooth it with an old kitchen spoon or a mason's trowel for a neat appearance.
An alternative to waterproofing compound is interior drain channel, which resembles square-edged plastic pipe. Although drain channel does not plug leaks, it collects water seeping from the seams around the basement floor and carries it to the drain at the lowest point in the floor of most basements or a sump pump.
If the walls are solid masonry, install the channel by cementing the sections to the floor and against the wall, using the sealer provided. Water seeping from the seam will flow into the channel.
If the walls are hollow concrete block, drill small holes into the bottom row of blocks before installing the channel. The holes allow water that collects in the blocks to drain.
After making these repairs, walls can be further waterproofed by applying masonry sealer, a penetrating paint containing cement and sealers like synthetic rubber. Before applying, prepare the walls by removing all old paint and washing the surface with muriatic acid solution to remove powdery salt deposits, or efflorescence.
When using acid solutions, wear rubber gloves, eye protection and suitable clothing. Follow all instructions on the container.
Apply the sealer with a masonry paintbrush. Adequate ventilation is necessary, and the temperature in the basement has to be above 50 degrees.
Work the material into the pores of the surface at the coverage rate specified by the manufacturer. Cover the bottom third of the wall and areas of general seepage first.
Wait 24 hours for the compound to dry, and then apply a second coat over the entire surface.