Most ways of waterproofing basement walls deal with the inside and outside of the wall. The best time to make sure your basement is waterproof is during construction when a waterproof membrane can be applied to the outside of the foundation. Leaks and seepage through your basement walls could result from poor original work, the home settling, or hydrostatic pressure from changes in the water table around your home. Some work is required in order to waterproof your basement walls.

Do there appear to be any hairline cracks, holes, or other porous areas in the walls? With just a waterproof mix, smaller holes and cracks will be fine but larger holes will need to be filled with mortar and then waterproofed. Chisel out a dovetail to allow the mortar to properly take hold from the inside when filling in larger holes. Mortar is usually one part cement to two parts sand with enough water to make a stiff mix.

There should be air holes or pockets and an ordinary trowel when applying mortar. If the wall is leaking considerably you may need to put in a drainage pipe to a sub pump to help drain the water and before applying the mortar, use a stiff wire brush to get rid of loose particles which will help it adhere. This may only be temporary or permanent depending on the nature of the water flow. Leaking floor joints and larger holes in the wall should be repaired in much the same way.

To help it adhere, chisel out a dovetail joint and provide strength and drainage by inclining the patch slanting it from the floor to the wall. We are ready to apply the waterproof mixture after repairing the wall. The mixture does not adhere to a dry wall, but will not set on a wet wall either so remove any paint and mist the wall before applying it. Epoxy and latex waterproofing mixtures usually require the addition of some water, so be sure to read the manufacturer’s instructions carefully but you may also use your own mix of plain cement and water mixed to a slurry about the consistency of cream. Use a stiff brush to apply the mixture at the bottom of the wall and move up in a right to left direction.

Make sure to get it into every nook and cranny. After the wall has dried overnight wet it down thoroughly again and apply a second coat of the waterproofing mixture in the same manner as the first. You may have to start over again if you use one coat instead of two as this will not do the job. Use this information and you will find waterproofing basement walls is not as difficult as it first appeared. Ultimately, the dry basement you have been wanting for quite some time will be ready.