Foundation footing drains are required in most areas where ground water may be problem. Footing drains if properly installed will keep ground water from building up outside the basement walls and avoids having the water penetrate into the living area inside. We will discuss both new and existing foundations. New foundations where a full basement is present, requires that a coating of waterproofing be applied to the wall areas below grade to keep water from penetrating through the wall. If the foundation is constructed of concrete masonry units, a coat of cement plaster is also required before the waterproofing is applied. At the exterior bottom of the foundation wall a “cant” is installed using either mortar or a pre-made fiber material. A cant is shaped as a triangle and helps shed water that runs down the foundation wall, and forces it away from the wall and into the footing drains. The contractors excavator must dig a “tail” ditch from a foundation corner to a point lower than the footing where the footing drain can exit at daylight. This distance may be only a few feet or perhaps a hundred or more feet. The tail ditch slopes downhill the entire way to assure good water flow. The excavator will now place a three inch or so layer of three quarter inch gravel all the way around the foundations exterior approximately twelve inches wide. Once the gravel is flatted out by hand, the finished height should be just below the interior basement floor elevation by about five inches. It is not necessary to compact this gravel. The contractor then installs four inch PVC piping laying it against the side of the concrete footings with the necessary ninety degree elbows to complete a closed circuit until it reaches the tail ditch outlet corner. There, a Tee fitting is installed to allow the pipes to be joined coming from both directions and also leaves an opening for a third pipe to exit the tail ditch.The PVC pipe used around the foundation is perforated with two rows of holes on one side. These holes face downward when finished. Do not let anyone talk you into leaving the holes face up for the water “to fall into”. It also allows all the sand, silt and earth that washes down from above to fall into the pipe and thereby quickly plug it solid. Water when building up around the foundation will find the holes on the bottom of the pipe and will easily enter into the pipe void. Since water seeks it own level, with the drainage piping installed at a slight downward slope, the water will flow to the lowest exit point. Even if the footing drain piping is installed dead level, the tail ditch which is on a down slope, will allow the water to flow to the daylight end of the pipe. It is the path of least resistance. It is much easier for the water to follow the pipe then to push through a small crack in a foundation wall or floor.