What type of egress window well cover is required by New Brunswick building code to prevent water and debris from accumulating in the well?

The NB Building Code does not mandate a specific type of egress window well cover — but this doesn't mean covers are optional in a New Brunswick context. Drainage performance of the window well itself is the code's primary concern, and in NB's climate, an uncovered well is a serious practical problem.

What the Code Actually Requires

The NBC (as adopted in NB) requires that egress window wells have adequate drainage to prevent water accumulation against the foundation. The well must connect to a drainage system — typically the weeping tile or a gravel bed draining to daylight — so that water doesn't pond against the window and force its way into the basement. The code specifies the minimum opening size (3.8 sq ft clear opening, maximum 1,500mm sill height from floor) and that the well must allow unobstructed egress in an emergency, but it does not prescribe a particular cover style or material.

Why Covers Are Critical in NB Regardless

NB's Maritime climate makes window well covers a practical necessity even if they aren't a specific code requirement. Spring snowmelt and heavy rain events — common from March through May — can overwhelm even a properly drained well and drive water directly against the window frame. Leaves, pine needles, and debris accumulate quickly in NB's forested residential areas and will clog the gravel drainage bed at the base of the well within a season or two if left uncovered.

The most important rule is that any cover you install must not impede emergency egress. A cover that requires a tool to remove, or that locks from the outside only, defeats the life-safety purpose of the window entirely. Covers should be designed to be pushed open easily from inside without special knowledge or strength.

Practical Cover Options

Polycarbonate dome covers are the most popular choice in NB — they're transparent (preserving natural light), shed snow load well, and hinge or lift off easily from inside. Flat grate-style covers (metal or plastic grid) keep debris out but allow rain and snow in, so they only work if your well drainage is flawless — not a safe bet in NB spring conditions. Custom-fit bubble covers sized to the well diameter offer the best weather protection.

Practical Tips

Check with your local building inspection department (Moncton, Fredericton, and Saint John have their own departments; rural areas go through the Regional Service Commission) before finalizing your well and cover design. Some municipalities have adopted local amendments or have inspectors with specific expectations around drainage documentation. When your egress window installation is inspected, ask the inspector directly whether your cover choice is acceptable — that's the definitive answer for your specific location.

Also ensure the base of the well has at least 6 inches of clear gravel connected to drainage, and that the well extends at least 8 inches above grade to prevent surface water from spilling in over the top.

If you're having an egress window installed as part of a basement finishing project, New Brunswick Basements can match you with a local contractor who knows the inspection expectations in your municipality — the matching service is free.