Exterior Membrane Waterproofing is the most popular method used by basement waterproofing companies to stop a basement leak, particularly when the leak is just in one area of a finished basement. Usually, this kind of leak is one that we can repair without needing to tear your beautiful basement apart.
The problem is often just a small crack in your foundation that shrinkage caused, and we usually can repair the leak in the basement by immediately excavating around the area that is affected, about 5 to 6 feet all the way down to its footing. Diagnosing leaking or wet basement problems properly can help with minimizing other expensive basement repairs. Read our basement leaks in heavy rain article.
How Leaking Basements Are Repaired By Basement Workers
This process begins with getting the exterior leaking wall of the basement cleaned and dried. The crack is sealed with polyurethane and then a drainage membrane is installed and sealed (an air gap is created by the drainage membrane between the wall and wet earth to prevent Hydro Static pressure and to keep the wall dry). It results in water running down to its weeping tiles and then drained away. We only test the weeping tile and replace it if it is necessary.
Waterproofing systems all rely on there being adequate drainage at the foundation’s base. Without this, Hydro Static Floor Pressure can cause water to go up through the perimeter and the floor and wall cracks.
Common Causes Of Basement Leaks
Weeping tiles, in our experience, cause less than 2% of all of the waterproofing projects that we do. Water basically will follow a path of least resistance. When water seeps in between the earth and your foundation it begins to back up due to the dense soil. When the water backs up Hydro Static pressure is created against the foundation. This usually isn’t a problem unless the wall has a crack in it, and then water gets forced through the crack.
Whenever water reaches a functioning tile system’s gravel bed it loses all of its pressure and then gets channeled to the tile channel. When a drainage membrane is extended from the ground level over to the weeping tile system it eliminates the chance of Hydro Static pressure building up on the membrane’s interior at the wall, and prevent a leaky basement.
Other Things To Consider
There are some customers who think they need additional protection like a Blue Skin Membrane that is glued onto the wall before the drainage membrane. Check with your local waterproofing provider to see what their guarantee is. In areas where it isn’t necessary to excavate down to the footing like voids, holes, top rod, and inlets near the grade, we utilize a combination of Styrofoam, Aqua Block, Blue Skin, and Hydraulic Cement.
We do not use a drainage membrane because we do not have to excavate to the weeping tile. So make sure you get in contact with a waterproofing company to see they can help repair your leaking basement.