How Does It Work – Interior Waterproofing


Interior waterproofing refers to a technique where the wall of a basement is made impermeable to water. The purpose of interior waterproofing is to prevent moisture and water from entering your living space and causing stress and discomfort. It also prevents moisture and water from turning your basement floor into one giant Petri dish to promote the growth of fungi. This can be accomplished through painting with “waterproof” paint, or using vapor barrier plastics or other methods. Vapor barriers are ideally sheets of solid plastic/ vinyl applied to the foundation wall to help keep moisture out so that you can enjoy your interior living space.

Interior Waterproofing How Does it Work?

  • Products such as Drylock, Watertite, Damplock are made of a material that will not allow water to seep in. This is painted on the interior wall, when it is not wet. As it dries it makes a seal on the wall to prevent any more moisture from entering.
  • Vapor barriers are pieces of plastic or vinyl that are glued or attached to the interior walls to keep out moisture.
  • If you want to give your walls a nice look as well as waterproofing, you can apply a water resistant material like Drylock. Then add a layer of foam insulation directly on the wall. Tape the seams of the insulation so air cannot get in. This prevents condensation from forming.

Which method is best?

  • The paint-on type products will work for a while but as the product ages it will begin to loosen from the wall and allow moisture to begin to seep in again.
  • Vapor barriers will last longer, however eventually tiny particles of water will form and begin to break down the plastic or vinyl.
  • The foam insulation is the longest lasting of the three methods. But to insure your basement stays dry you need to check into exterior waterproofing to stop the water where it starts.

Interior waterproofing is a technique used to keep your basement walls and floor dry. With interior water-proofing, water is barred from entering your living room space and causing problems. Most interior waterproofing projects can be done without the help of a contractor. However you may want to consult a professional before you begin to help determine where the problem originates and what the best option is for your home.