FOUNDATION & BASEMENT WATERPROOFING IN THE SAN FRANCISCO BAY AREA

Foundation Waterproofing is a general term that is descriptive of the range of professional services performed to repair a basement that is wet. Frequently, inquiries are made as to “How much does it cost to waterproof a basement?” That is like taking your car into an Auto Repair Shop and asking, “How much will it cost to fix my car?”

Foundation waterproofing is the process of preventing water intrusion, whether it be from subtle water seepage or from flooding when the ground is over-saturated. For home and business owners in the Bay Area of Northern California, this is an especially concerning problem due to the varying weather patterns that occur in this area. There are a myriad of approaches and products for waterproofing a foundation or basement and there are some strong opinions of one method over another, so you’ll hear a lot of suggestions about what to do if you are seeking answers to a wet basement or are having water intrusion issues with your foundation. Like many home and business repair projects, foundation and basement waterproofing issues can seldom be resolved with a single product or treatment. That’s why it is important to always call an expert in foundation waterproofing and moisture control at the first sign of a problem. Contacting a contractor who specializes in designing waterproofing systems to fit your individual needs is recommended by most industry experts.

In foundation waterproofing, the first step is to identify the source of the leak in the wet basement. This usually is done by conferring with the home or business owner to determine when and where the problem began to occur. It helps in the diagnosis if the basement is unfinished because water leaves a trail. However, a well-trained Basement Advisor can also help find the source of the problem in a finished basement.

WATERPROOFING SOLUTIONS IN THE BAY AREA

Wet basement solutions come in a variety of strategies, most involving the sealing of the foundation wall cracks in poured concrete foundations (poured concrete is the most common type of foundation in the Bay Area of Northern California). Cracks are easily visible in an unfinished basement. These leaking cracks leave water stains on the foundation wall. However, in a finished basement, the diagnosis should begin by identifying the area where the water is first entering the basement, then searching around the exterior of the structure for a crack. A good number of these cracks extend to the top of the foundation wall, which is normally exposed above the soil line. Cracks can also be sealed from the interior using an Epoxy / Urethane injection process or from the exterior using a Wall-Clay process. Both methods are reliable in preventing additional seepage through the crack and into the basement.

There is another common basement waterproofing problem where the source of the water leak is at the cove joint where the floor and wall meet. This is frequently caused by hydrostatic pressure, which occurs when the water table rises after a long period of rain or snow melt. The accumulated weight of water in the ground (8 pounds per gallon) forces water underneath the structure’s footing and up into the basement. The best solution for this type of problem is the installation of a Drain Tile System, where a sump pump is used to discharge the water. The drain tile (sometimes referred to as a French drain in other areas of the country) relieves the hydrostatic pressure by providing an easier path for the water to escape, thus eliminating the water’s pressure so that the seepage problem goes away. This problem can be addressed from either the interior or exterior of the structure.

FOUNDATION WATERPROOFING AND GRADING ISSUES

Sometimes a diagnosis will show water coming in over the top of the foundation or through the mortar joints between the bricks that sit atop the foundation wall. This problem happens as a result of the exterior grade being built up above the top of the foundation wall, either by soil or, possibly, by a previous construction of a driveway, a walk area, or a patio. This can be readily confirmed by running a garden hose on the ground beside the problem area. Warning: water will often enter the basement rather quickly, so it is recommended that you be ready to turn the water off quickly.

Unfortunately, lowering the grade is not usually a viable option in this situation. It is usually recommended that an Exterior Subsoil Membrane be applied to the lower graded portion of the wall when this problem is encountered. The solution only needs to cover the wall from the soil line down and then overlap the foundation by only about 6 inches. Foundation waterproofing membranes are also effective for waterproofing brick, stone, and other hard surface foundations.