Building codes call for a window well that sits at least eight inches below the bottom of the window and extends six inches past each side. A quick way to get the minimum dimensions is to add 12 inches to the window’s width and eight inches to its height. For egress windows, most areas require a minimum of 36 inches by 36 inches and a depth of approximately three to five feet to provide a safe emergency exit.
Adding a drain is the best way to keep water from pooling in the well and leaking into the basement. Connecting the well to a French drain or sump pump channels runoff away from the foundation, and proper grading supports the system by directing water downhill. If you notice standing water or moisture, talk with a pro about upgrading the drainage before it compromises the structure.
Plan to replace the window well once you notice persistent leaks, water pooling, rust, or cracking—any indication that the well is no longer protecting the basement. Handling the project quickly safeguards the foundation and avoids costly repairs down the road by stopping moisture before it spreads. Consult a window installation pro for an inspection to see if it’s time to replace your window well.