What size does an egress window well need to be?
An egress window well needs at least 9 sq ft of horizontal area, with a minimum projection and width of 36 in (IRC R310.2.3).
A window well serving an emergency escape window must provide at least 9 square feet of horizontal floor area, and must be at least 36 inches in both width and projection (the distance the well extends out from the foundation wall).
The well also has to be sized and shaped so the window can open fully and an occupant can climb out — a well that blocks the sash from opening does not comply.
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Ask Donnie →General information based on the International Residential Code (a model code). This is AI assistance to verify — not legal advice. Confirm the adopted edition and any local amendments with your local building department (AHJ) and a licensed professional before you build.