How Do You Waterproof a Block Foundation from the Inside

DO apply a masonry waterproofing product to bare interior basement walls. If your foil test showed that water is soaking through your basement walls and leaving them wet, seal the interior of the walls with a high-quality waterproof paint, such as DRYLOK White Extreme Waterproofer (available from Home Depot).

Can you waterproof foundation from inside?

Apply a masonry waterproofing product to the walls Seal/coat the interior of the walls with a suitable masonry waterproof product. When the paint dries, the sealant forms a watertight bond to stop water from seeping through. This is how you can waterproof your basement walls from inside.

How do you seal interior cinder block walls?

You can use a product like RadonSeal Plus Penetrating Concrete Sealer to help waterproof and preserve the overall look of your wall. It will help permanently block the elements like moisture and water. It’s fairly easy to apply if you know your way around the house.