A window well is a square or semicircular embankment dug on the side of a house to make room for a window close to the ground. Window wells are used when windows are built level with the foundation, or in basements, where the window needs space away from the soil and enough access to sunlight and air to make the project feasible. A window well is usually excavated for every window at or below foundation level, but they are sometimes long, running excavations that may cover multiple wells. These wells are usually shored up by a cement brace or brick wall of some sort, and extend up to several feet down into the soil.
One problem with window wells is that they attract water and debris. Dirt and leaves blow into the wells and cannot escape, so they must be cleaned out. Rain water and snow accumulates inside, which can lead to deterioration and leaking problems. Most window wells come with a few inches of gravel, which is often not considered enough to adequately deal with drainage problems.
This leaves several other possible solutions open to the homeowner. One is to install a simple drain that diverts the water down to the natural foundation drains built under and beside the house. This can be problematic with basements because the water is encouraged to flow toward the house instead of away from it, which makes it easier for leaks to develop.
A more complete solution is to create a series of trenches or outlets built into the window wells that divert the water away from the house until it reaches a point where it can be safely drained into the soil. The problem with this process is that it can be expensive, and may interfere with landscaping.
Some contractors suggest digging down even deeper into the well and adding about a foot of gravel to help with drainage problems. This solution is appealing because it does not affect surrounding construction or landscaping as much.