A Home Owners Guide to Basement Waterproofing
As a basement waterproofing company in Columbus, Ohio, we know if the job isn’t done right the first time, this can lead to issues that could have been avoided in the first place. Waterproofing is critical in the well being of the structure.
A common issue we see when inspecting basements in Central Ohio is seepage. Seepage can cause extensive damage if it is not addressed properly. Sometimes people will attempt to apply a coat of sealant inside the basement when the actual problem comes from the outer walls. Let's walk-through how to waterproof a basement.
1. Dig around the basement perimeter
This is going to require more than just a shovel. To fully protect your basement from water, you will need to dig the outer perimeter of the basement all the way down to the base of the foundation. By digging you can have the right product applied over the walls which is key for keeping water out. Drainage tiles, gravel/crushed stone drains, perforated pipe, or other approved systems/materials needs to be installed at or below the area to be protected then discharged into an approved drainage system.
2. Check basement walls for cracks
Now that the excavation is completed, clean the wall and check for any cracks or areas that may be letting water in. If you find any cracks or problem areas, apply a coat of hydraulic cement to the walls to stop the leakage. Hydraulic cement will expand as it cures and it will fill in the cracks and voids reducing the probability of leakage.
3. Apply sealant to the basement walls
Apply a coat of cement based sealant to all exterior walls. Cement based sealants are easy to apply and can be used over multiple surfaces, like concrete and masonry. Cement sealants will harden and will close the concrete pores. If a hairline crack was not fixed in the previous step with hydraulic cement, it will be covered in this procedure.
4. Apply a waterproofing membrane
Time to install a waterproofing membrane. A coat of the membrane, an asphalt-modified polyurethane material, can be troweled or sprayed on to seal the foundation wall against water from the outside. Make sure there is a sufficient amount on the walls. Elastomeric membranes are made of modified asphalt and exhibit great waterproofing abilities.
A benefit that comes from elastomeric membranes is that they can flex and move to accommodate when new cracks occur. Make sure to use a waterproofing product instead of a damp-proofer product, as the damp-proofer has the tendency to fail.
5. Install a basement drainage mat
You might be asking, “what is a drainage mat?” A drainage mat is a sheet of semi-rigid plastic that comes in a roll. The plastic has an egg-carton shape, with protruding dimples. When placed against a concrete wall, the dimples make the plastic stand out from the wall, leaving a free-draining air space between the plastic and the concrete. If any water reaches this air space, it easily flows to the bottom of the mat. Now that you understand what the mat does, it’s time to install it. The drainage mat should be cut to the exact depth of the foundation. It can also help ease lateral pressure against the foundation.
6. Install a French drain
Here’s the final step of the process. Install the French drain or weeping tile. The pipe, which should be 4” in diameter is recommended, must be installed at the base of the footing weeping the water level below the basement floor. It is helpful to install cleanouts, which allows easy access for maintenance purposes. Backfill with gravel. Gravel should be 18″ from grade for earth areas, and 4″ from grade where cement will be poured.
7. Things to avoid when waterproofing
Now that we showed what to do, here are some things we don’t recommend when waterproofing a basement:
Don’t use tar. Tar will becomes brittle and will crack at some point.
Don’t use plastic to waterproof your basement walls. The plastic-like material will peel, and water/moisture will make its way in.
Don't use limestone to backfill. Limestone will reduce drainage and could clog all drainage structures. Use gravel instead.
Water coming into your basement? We at Ohio Basement Pro have years of experience when it comes to waterproofing. We are fast, thorough, and affordable. Give us a call at (740) 262-3423 if you need help waterproofing your basement in Columbus, Ohio.