How to Waterproof Your Basement

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Here’s a step by step procedure on how to waterproof your basement:

  1. Examine your house’s perimeter. The ground next to your foundation should slope away from it. That’s a rule of the thumb. If it’s towards the foundation, you’ll have a problem. The dirt around it will just cause the ground to sink in and move towards your home. If you must, you can add dirt against the foundation and create at least two inches per foot slope against it. Ensure that the top of the added dirt is at least seven inches below the sill plate. This is one way to make sure that there’s no ground contact since that can cause some building materials to rot in the long run.

  1. Clean and check.

Don’t forget to clean your gutters and check if water is being discharged by the downspouts at least 1.5 meters away from your foundation. Otherwise, you’ll have problems.

  1. Check your foundation; it shouldn’t be too close to plants and shrubs.

The rotted roots of plants and shrubs can make a pathway for surface water to slope down your foundation. It’s best to keep plants away from the foundation at least a foot away. Keep them on a slight slope so they could regulate the water away from the foundation.

  1. Waterproof your walls.

You can do this with products such as Xypex or Drylock. They are ideal for small intermittent leaks. Using Xypex is like spreading a waterproof concrete on a surface and letting them bond. This product depends on the existence of moisture in the formation of its waterproof crystalline structure. If its application has tiny areas of water leakage, don’t worry, the Xypex will seal itself while they cycle through moisture. It’s more expensive than Drylok, though; it costs about 2-4 times more. Drylok, on the other hand, expands as it dries in order to bond with the wall. Take note: It’s a waterproofer and not a water sealer. The only downside of using these solutions is that the groundwater found at the bottom of your walls or under the basement floor will be under serious pressure because of the groundwater weight above it that’s pressing down.

  1. Repair.

The next thing to do is to look for defects like cracks in the concrete walls and also in places where form tie rods and pipes go through the concrete. Repair the cracks, if there are any, using a construction-grade epoxy. An injection will do. It can pass through the crack from the inside out. If the crack won’t undergo through any structural or thermal motion, you can use Drylok Fast Plug. This effective plug is used to seal cracks in the masonry. It’s highly recommended to call an experienced crack repair technician for the job. Sure, DIY kits of polyurethane systems and epoxy are accessible, but they’re not so reliable. You wouldn’t want to mess up this crucial step because a single crack on the wall can be a potential source of water.

  1. Install a sump.

This is optional but highly advisable. Installing one will require moderate skills because you’ll need to jack hammer or create a hole in your basement floor, excavate that hole, place a liner in it, wire the sump pump, and plumb an outlet from the pump to the outdoors. Allow me to explain how a sump and a pump works. Once the water level in the sump becomes too high, a pump will kick on and draw the water out of the sump, releasing it 10 or more feet away from the foundation outside your house. Calling an expert for this step is also suggested.

  1. Use a French or perimeter drain.

If you have serious water issues, use a French drain. This has a continuous system of piping which runs beneath the floor of your basement and along the perimeter of your basement. Its installation is like that of a sump. However, you’ll need to cut and remove 12” wide strip of basement floor along the entire perimeter of your basement, dig a trench that’s 12” deep, fill the trench with coarse gravel surrounding the drain pipe, then re-pour concrete floor to cover everything.

A French drain always includes a sump and pump for the removal of any water that gets into the drain system.

  1. Inject Hydroclay.

An installer should to this final step. Hydroclay should be injected around your foundation to absorb plenty of water. This clay, which is a waterproofing version of Bentonite Clay, fills in voids and follows the pathways which water uses to get to the inside of your foundation, sealing the basement for good. This clay is normally pumped from the outside and is similar to the product used for waterproofing dumps, manholes, tunnels, elevator pits, and backyard ponds.