How to Waterproof a Concrete Basement Floor

The concrete basement floor is often neglected while waterproofing the basement. Unfortunately this is, of course, a terrible mistake as the concrete basement floor is the one area of the basement where water will flow to naturally. This is the reason why most builders create drain areas in obscure places in the basement floor that lead down a concrete shaft to the soil under the home. The walls are usually the location where the water begins to come in to the basement but it rests on the concrete basement floor to pool and erode the concrete. In good home construction the exterior of the basement walls are coated with waterproof paint and drainage is in place. You can waterproof your concrete basement floor yourself and the information below will show you how.

Step 1 – Prepare the Concrete Basement Floor

When you want to waterproof the concrete floor of your basement you have to make sure it is ready for the process. Make sure the floor is swept clean so the paint will be able to set without voids. Walk the floor and look for cracks and holes in the surface of the floor. Use the wire brush to sweep away at the sides of the cracks. This will remove loose concrete you can then suck up with the wet and dry vacuum.

Step 2 – Patch the Concrete

For the concrete basement floor to be effectively waterproofed it has to be patched as any crack could be an access point for water. Read the instructions on the bag of concrete and mix it with water in the bucket. Use the drill with the mixing attachment until the concrete is the consistency of oatmeal. The holes and cracks in a concrete floor are often small and patching them with too much concrete is a waste of time and money. Once the concrete is mixed fill a pastry bag with it and fill the cracks and holes. Let the concrete overflow and use the trowel to spread it out. Doing this will fill the cracks and holes but will also anchor it to the main floor. Wait for the concrete to dry, then sand it until flush with the floor.

Step 3 – Edging

The edges of the concrete basement floor have a tendency to separate from the walls in older homes. Take a preemptive measure and put a bead of concrete along the edges of the floor using the pastry bag full of concrete. Once the concrete has dried, tape the seams with silicone tape and then cover with concrete.

Step 4 – Painting

The final step in waterproofing your concrete basement floors is painting them with waterproof paint. Mix the paint well and pour it in to the paint tray. Use a regular paintbrush to apply the paint to the floor so you do not neglect any divots. You can use a roller to even out the paint or to apply a second coat if you like.