Old House, Wet Walls: Fixes For Rain Moisture In Your Basement

If you have an older house with a brick or rubble foundation, the basement can really seem like a dungeon because of darkness and moisture. If you haven't yet finished your basement and notice that the stone or brick walls seem damp to the touch after a big rainstorm, you need to look into basic waterproofing techniques to help make your home more weather resistant. 

First, make sure that outside water is the problem.

Sometimes, basement walls can seem damp just because the cooler brick buried below ground allows for indoor humidity to condense on the surface -- leading to dampness and old growth. Since humidity accompanies rain storms, you might think you have a leak, but really you have an indoor moisture problem. Be sure to tape a piece of tin-foil to your basement wall to find out the true source of the wetness. After a day or so, water behind the foil will mean exterior water problems, while water on top of the foil will mean indoor humidity trouble.

Look for cracks and entry points.

Easier fixes come from sealing up cracks in the brick or rubble. Older homes settle over the decades, and small cracks in the basement are not uncommon. Use a waterproofing foam sealant to fill cracks with expanding foam. Water can seep through cracks. Sometimes, sealing and using a waterproof primer on the interior walls is all that is needed.

Another entry point is through basement windows. Check your window wells to make sure they are properly excavated -- sometimes, old window wells can fill up with dirt and the water can seep up under the frame if the dirt is close enough to the window base. 

Start more aggressive waterproofing options.

After sealing up cracks, it's time to start looking for other ways to keep your basement dry. Usually, this means redirecting rainwater flow away from your home in a number of simple ways, including:

  • fixing gutters and downspouts to make sure that rain from your roof is directed away from your foundation. 
  • grading your property to slope away from your home. 
  • installing weeping tile around your house to direct water to the street or another area of your property. 
  • having your gutters, sewer lines, and foundational trenching inspected to make sure they are still functional. 

The above fixes are usually quite effective in fixing rain issues. If the exterior water table is high, however, water will eventually enter your home through porous rock and masonry. The reason why the water problem seems worse after rain is because the saturated ground becomes even more saturated, and the pressure of the underground water moves into the basement because it has nowhere else to go. In these cases, you should also:

  • install a dry well on your property. This gives the water somewhere to go other than your foundation. The well is quite deep, and when it rains, it provides a void for groundwater to flow into, instead of flowing into your basement. 
  • have an interior drain system. It may seem strange to create an entry point into your home, but think of it as controlling the chaos. Water can flow into a pipe surrounding your home, and the pipe can empty into a drain inside your basement, where it flows to the sewer with the rest of your waste water.
  • install a sump pump. This is like having a dry well in your own home. When water does leak into the basement, the sump pump turns on and pumps it away from the house. A sump pump is lower than the rest of your basement, so this is where extraneous water goes first. If flooding is a major concern, two sump pumps are better than one. 

For more information and options, talk with a professional waterproofing service, such as Champion Waterproofing.