Basements are one of the most neglected parts of a house. Most of the times, basements are used as storage of old, unnecessary items. However, basements could be transformed into dry and cozy room, not much different from a living room, dining room, or even bedroom. The only difference could be the basement’s lack of outside view.
Leaks and Seepage–the Most Common Basement Problems
The ground in most places acts like a sponge. It readily collects and holds water. This is why when artesian well’s pipes are pushed deep into the ground, water can be easily drawn out, or in some cases it just oozes out like a fountain. This is due to the amount of water stored in the ground.
In some locations, especially in low lying areas, water can be present just a few centimeters deep in the ground. This is called high water table. A water table is where the atmospheric pressure equalizes with water pressure. In an excavation, the limit of the water table is marked by wetness of the soil that runs horizontally.
Any house built on locations like this need waterproofing to seal the part of the structure that will continuously be in contact with the ground. The lack or insufficiency of waterproofing can wreck the foundations of the house, and is the most common cause why water seeps through the cracks and joints of the basement floor and walls.
Rehabilitating by Basement Waterproofing
In rehabilitating the basement, the most important work is to seal the basement with waterproofing. There were three different methods used to waterproof a basement depending on the severity of the leakage:
Interior Sealing:
This method of waterproofing a basement is done from the inside of the house. This stop-gap method is mostly used to contain local water leakage from pipe penetrations on the walls, cracks and joints between the footing and the mason of the basement using cement-based sealants. This waterproofing method is less costly, but cannot last long.
Interior Drainage:
Although this method is technically not waterproofing, this elaborate method has been long used in mitigating water from intruding into the basement floor. This method is accomplished by excavating portions of the basement floor perpendicular to the basement wall and laying a series of French drain beneath the basement floors. French drains are perforated pipes that draw water from the soil. The collected water is then channeled into a sump water tank equipped with a pump to take the water in to the surface into the sewers.
Likewise, a drainage layer is added to the basement’s wall face, behind the wall finish, to collect the water leakage from the wall. The emplaced French drain is then covered in gravel to ensure that the soil won’t get into the perforation of the pipe. Thereafter, concrete is poured into the floor to repair the area that was excavated.
However, a gap is usually left out where the concrete footing, floor slab, and the masonry walls meets. The water collected by the drainage mat is passed through this gap into the soil below.
Exterior waterproofing:
This is the most elaborate, labor-intensive and most expensive method of basement waterproofing. This method requires excavation of a trench around the basement in order, to clear the outside walls of debris and dirt. Likewise, a thorough inspection of the walls surface is required to identify opening that may cause leakage to the interior of the basement.
Thereafter, the application of waterproofing materials that includes cement-based sealants and elastomeric waterproofing materials ensuring complete all around coverage. Moreover, the installation of French drain along the concrete footing is necessary to collect the water that is trapped by the waterproofing. Finally, the trench is filled back with gravel. Moreover, the area is covered with soil to allow landscaping.
The combination of the last two methods is deemed by many waterproofing experts as the most effective way to counter the hydrostatic pressure coming from below the basement and the seepage from the soil surrounding the basement. This frees the basement from any leakage and seepage that come from ground water.
