Window Well Requirements for Egress Windows

When an egress window is installed below exterior grade level, a window well is required to provide clear access to the window from the outside. The window well must be large enough to allow egress and must drain properly to prevent water accumulation that could block escape.

IRC R310.2.3 Window Well Dimensions

A window well that is 36" deep (projection from wall) × 36" wide provides exactly 9 square feet — the minimum. Larger is better: a 48"×48" well provides 16 square feet and makes egress significantly easier for both occupants and emergency responders.

Window Wells Deeper than 44 Inches

If a window well is more than 44 inches deep (measured from the bottom of the well to the finished grade at the top), it must have permanently attached, built-in steps or a ladder. The steps must be usable in the dark, in an emergency, without special knowledge. Pre-manufactured window well step kits are available from most building supply stores and are the most code-compliant solution.

Window Well Covers

Window well covers are permitted by the IRC and recommended to prevent debris accumulation and water infiltration. However, covers must be openable from the inside without the use of tools, a key, or special knowledge. Solid polycarbonate or metal grate covers with simple lift-off or quick-release latches are acceptable. Covers that require tools to remove, are padlocked, or are bolted down are not acceptable — they block emergency egress and will fail inspection.

Drainage Requirements

Window wells must drain properly. Water pooling in a window well can reach the window threshold, allow infiltration, and in severe cases, prevent the window from opening. Code requires that window wells drain to the foundation drainage system, to a gravel sump, or to daylight. Most contractors install a gravel bed at the bottom of the well (typically 6-12 inches of clean stone) that drains to the foundation perimeter drain. Confirm this connection is made — a gravel bed without drainage connection just delays, not prevents, water accumulation.

Common Window Well Problems

• Well too small: Less than 9 sq ft of horizontal area — requires enlargement
• No drainage: Water pools and infiltrates — install perimeter drain connection
• Cover with lock: Cannot be opened from inside — replace with quick-release cover
• No ladder in deep well: Well deeper than 44" without steps — install well step kit
• Retaining wall too close: Landscaping or retaining wall encroaches on 36" projection — may require regrading