Basement waterproofing has become increasingly popular as homeowners have sought to convert rough basement space into living space. Waterproofing techniques and strategies can be grouped into two major categories: External and Internal. In this article we will explore popular methods and techniques of waterproofing basement walls externally.
Why waterproof your basement walls externally? Isn’t it true that internal waterproofing is more popular and cheaper? Well generally speaking, yes. Internal methods are very popular and many of them can be extremely affordable. However, strictly speaking internal basement waterproofing is not really waterproofing at all because you’re not preventing water from entering the basement walls. Rather, you’re devising methods of dealing with the water once it does enter. On the other hand, when you waterproof your basement walls externally you are actually preventing water from entering them in the first place. This is important because water is naturally destructive to building materials. Over time constant water exposure breaks down the composition of any material even the mortar and block of which most foundation walls are built.
There is also a third strategy known as diversion which can be thought of as an adjunct to drainage. Drainage means you’re installing systems to drain water from the ground surrounding the basement. Considering that water follows the path of least resistance, you’re giving the water an easier path to follow than to enter your foundation walls. Diversion systems refers to the rain gutters and downspouts on your house.
Exterior drainage systems are usually referred to as footer drains or tile drains. These systems are comprised of a channel that is dug around the perimeter of the foundation walls at a depth just below the wall footer. The channel is filled with an aggregate, in other words, gravel. In the middle of the aggregate lies a pipe. The pipe has perforations that allow liquid water to enter. As ground water descends it finds little or no resistance to entering the trench because of the abundance of air spaces within the gravel (aggregate). Once in the trench, the water also easily enters the pipe through the perforations. The pipe then leads to a remote drainage location such as a storm drain or a natural ground water drainage path.
A good exterior footer drain system benefits greatly from a good diversion system. As we mentioned earlier, a diversion system is comprised of the rain gutters and spouts on a building. You might be wondering why you need to worry about the rain water when you have an underground system draining water away from your house.
The reason is because water carries silt and other particulate matter dissolved within it. Over time, that sediment accumulates within the footer drains and begins to obstruct the flow of water. The more water flowing into the footer drains, the faster sediment will accumulate. A good diversion system will keep most rain water out of the drainage system. This is accomplished with gutters collecting water from the roof edges and downspouts emptying at least 5 feet away from the foundation walls onto ground sloping away from the house. Ideally, the downspouts will drain into underground pipes emptying into storm drains. The more rain water is diverted away from the footer drainage system the longer the system will last. A professional waterproofing service like Roofing Contractor Bronx always gives benefits for long term prospects.