Waterproofing Residential Foundations

Many times people use the terms waterproofing and damp proofing interchangeably. People also interchangeably use the terms waterproofing and interior water diverting. All of these terms sound like they accomplish similar goals, though they do not. Understanding these terms is critical if you want to keep your foundation dry and structurally sound. Knowing what these methods can and cannot do allows you to pick the best method for your home.

Years ago many homes were spray coated with solvent-based asphaltic products. These materials didn’t actually waterproof foundations, they damp proofed them. These asphaltic coatings only prevent the transmission of water vapor into the concrete. Waterproofing materials prevent the transmission of both liquid water and water vapor. Now, many so called waterproofing companies attempt to divert the water that damp proofing does not stop. These interior water drainage systems do not prevent water from coming through the concrete. They are designed around the fact that water is coming through the foundation. They divert this water to a sump pump that expels the water outside the structure. Obviously this is contradictory to the definition of what waterproofing is.

Expectations of Waterproofing

Basement waterproofing contractors usually provide some form of drainage system as one of their services to solve a wet basement or crawlspace. While drainage is critical to solving water problems, it is also crucial that homeowners understand the purpose and limitations of waterproofing their homes.

The definition of waterproofing is the process of making an area impervious to or unaffected by water. Residential waterproofing is necessary to allow basements and crawlspaces to become useful areas of the home. Basements can be converted to new living space without the usually damp and musty smells that generally accompany a basement. Methods of waterproofing include exterior and interior systems, each having their benefits and drawbacks.

Residential Waterproofing Methods

Residential House

Today, contractors commonly use rubberized asphalt coating, which they can spray on or apply as a peel-and-stick sheet product. Regardless of whether they use the spray or sheet form of rubberized asphalt, they must protect it from ultraviolet light by covering and shielding it when exposed to sunlight. Next are polyethylene sheet membrane systems. These systems consist of three layers with the two outside layers made of high-density virgin polyethylene, sandwiching a layer of recycled polyethylene.

You need to protect any of these systems you use from damage caused by backfill, insulate basements, and ensure water drainage away from the membrane. Soils with high water content produce significant hydrostatic pressures against foundation walls. This hydrostatic pressure can cause water to penetrate the smallest holes and cracks. Waterproofing actually consists of a waterproof membrane and drainage next to this membrane which moves water to the exterior drain located alongside the footing.

This system of waterproofing is even more important these days due to the fact that homes are sealed tight. Building homes tighter in order to conserve on energy increases the problems of mold and mildew growth because relative humidity increases inside the building envelope. Stopping water from entering a basement makes a true waterproofing system a must these days.  Waterproofing, not damp proofing or water diverting is the answer to a healthy and dry home. Knowing what repairs are necessary for your home is the key to making your home dry and safe. My Foundation Repairs will help find a local contractor near you.