Having a window in a basement is the best of both worlds. You gain the advantages of below-grade living—even temperatures, natural soundproofing, extra space—and combine them with the best thing about living above-grade: natural light from windows.
When finishing a basement with windows, creating and maintaining window wells is a necessary step. Just like preventing water infiltration, installing a subfloor, and insulating walls, installing a window well and a window well cover is one of those necessary first-step sub-projects that let you get to other projects such as creating living space for an apartment, building a home bar, or installing a home theater.
What Is a Window Well?
Older basements, if they had windows, kept the windows at a minimum and kept them small. The low light and controlled temperatures were necessary for long-term storage of canned goods, root vegetables, and other items. But modern homes have expanded the concept of a basement far beyond that of a storage area. So, the basements in these homes require larger windows, and more of them.
Without windows, a basement has far less utility as a living space. In many cases, the basement cannot be used as a living space, under the local building code.
Day-light basements have one or more walls at grade level. This means that you can walk straight out and be on the ground, no steps up necessary. The other sides of the basement will be banked up against earth. On the daylight side, window wells are not needed. You can install windows in a conventional manner.
More common are basements that, except for the upper foot or two, are fully underground. When you install a window in such a basement, you need to create a type of dug-out on the exterior. This dug-out area is the window well. The window well is your opening to the outside world and it brings air and light to the basement. In some cases, window wells must be of specific dimensions to allow for egress in case of emergency.
The term window well also refers to a product that is attached to the side of your house that acts as a wall to hold back the earth.
Why Basement Windows Need Window Wells
Window wells often start with sturdy and solid dirt sides but deteriorate with the elements. Rain, snow, ground drainage, and human and animal contact all contribute to the collapse of the window well sides. These sides might eventually collapse onto your window, as well.
Dirt banked up onto your window eventually ruins the window and even your home's structure. Dirt is a vehicle for termites and carpenter ants, both of which can burrow into your home's structure and destroy it. Water-laden dirt acts as a conduit to invite tree roots and water into your house.
Keeping basement windows exposed means that anything that is located outside and on-grade can potentially reach your window. Basement windows tend to get a real beating from water dripping off of roofs and from ground-flow rain, so they deteriorate quickly.
How Window Well and Well Covers Work
Metal or plastic window wells are the solution to a window well collapse. Window wells act like a permanent storm door for your basement window, providing extra protection for this high-impact area.
Window wells fit into an existing well. Window wells are curved or rectangular galvanized steel or polyethylene shields that attach to the side of the house, supporting the earth and blocking debris, leaves, and moisture from reaching the basement window. Window wells only help with debris and moisture at ground-level. Window well covers help with debris and moisture from above.
Window well covers are half-circular, bubble-shaped, or rectangular transparent plastic (polycarbonate) shields that attach to the top of window wells. Acting much like a greenhouse roof, window well covers are not waterproof but they do keep a majority of the moisture away from the window.
When Building Code Requires Window Wells and Covers
If your local building code requires that your basement window provide egress (access to the outside in case of emergency), then window well dimensions must be large. Not only that, egress window wells may need to have some type of step or ladder system for occupants to use for escape.
Horizontal dimensions should be large enough to allow the window or door to be fully opened. The total area of the well should be at least 9 square feet. Outward from the house, the window well should project at least 36 inches. The height of the well should be no more than 44 inches, as higher well walls are considered to be hindrances to escape in the event of an emergency.
As always, check with your local permitting office to verify building codes in your area about basement egress, window wells, and window well covers.