Window well drainage is a subject that very few homeowners think about, until their basements flood after heavy rains. When a window well has inadequate drainage, or if it has not been installed properly, accumulated water often pours right through the basement window resulting in a flooded basement within a very short period of time. Parks' Plumbing & Sewer, Inc. is a Chicago company specializing in flood control systems and can assess your window wells for problems with drainage and or flooding related to your window wells.
Window wells are typically constructed of galvanized steel; they must be installed whenever a basement window sill is at or below grade (the level of the soil adjacent to the window). The role of a window well is to prevent rainwater and surface runoff from flowing through a basement window directly into the basement. When rainwater and/or melting snow introduce a significant amount of water in proximity to a basement window, the window well contains the water and prevents the water from flowing towards the window. It also provides drainage for the water so that the water cannot accumulate by the basement window.
For the water that does enter a window well, there are generally two drainage provisions for dealing with accumulated water: a gravel layer and a window well drain. The gravel layer in a newly installed window well is typically 6 inches deep. In a typical window well, 36 inches wide, the window well can hold approximately 15 gallons of water before the water rises to a level where it will pose the threat of flooding your basement. When enhanced drainage is desired, a window well drain is installed, the top of which is generally beneath the top of the gravel layer. Proper window well drains are 4 inches in diameter and drain the water in the window well to the weeping tile system installed underground along the footing of the foundation walls. Window well drains in new construction consist of a length of weeping tile; in retrofit applications, PVC sewer pipe is typically used.
Some of the most common problems with window wells occur because the window well has been installed incorrectly, it was not sized correctly, it is not high enough, it has gravel layer contamination, and/or lack of adequate drainage. A window well that has been poorly installed is not mounted flush onto the foundation wall; as a result, water and sediment enter the window well from between the foundation and the edge of the window well. If the window well is not deep enough or wide enough or high enough, water and sediment can come through the window. Poorly draining window wells are the result of soil and debris contamination of the gravel layer in the window well. When the gravel layer is contaminated by sediment, the excellent drainage qualities of the gravel layer are lost; similarly, leaves, newspaper and plastic bags often prevent water from reaching the gravel layer in which the water was to drain. While a galvanized window well is intended to keep water out of the window well, when water does get in it must not be allowed to accumulate; therefore, the water must drain. Water entering a clean gravel layer will flow through to the bottom of the layer which is typically clay soil which doesn’t drain well. If little water gets into the window well, a gravel layer will provide sufficient drainage. In the event that a significant amount of water enters a window well, more robust drainage provisions are necessary. This is accomplished by installing a window well drain. A window well drain is a very efficient way of draining substantial amounts of water to the weeping tile system.
Parks' Plumbing & Sewer Inc. can address all of your window well drainage problems and also installs window well covers.