A light well is a recessed area in the ground in front of a basement window, allowing daylight and air to reach the basement or semi-basement. It’s essentially a ‘pit’ against the facade, lined with walls of concrete, masonry or plastic. The top is usually covered with a grating. A light well is also known as a window well or area well.
What does a light well look like?
A light well is a rectangular or semicircular recess:
Width — Equal to or slightly wider than the basement window
Depth — 40-80 cm from the facade
Height — From the basement window down to ground level
Bottom — Gravel or drainage for water removal
Cover — Walk-on grating or light grating
Functions
Function
Explanation
Daylight
Lets light through the basement window
Ventilation
Basement window can open for air circulation
Emergency exit
If large enough, usable as an escape route
Water management
Prevents groundwater from sitting directly against the window
Installing a light well — DI The six DIY steps for fitting a prefab plastic light well, in order.
Y
Prefab plastic light well (easiest)
1. Excavate — Dig a hole in front of the facade, deeper than the bottom of the basement window
2. Drainage — Gravel bed (20 cm) at the bottom + optionally a drain pipe to the sewer
3. Place the light well — Set the plastic unit against the facade
4. Waterproof connection — Sealant or butyl tape between unit and facade
5. Backfill — Fill around with soil and compact
6. Fit grating — Walk-on grating on top
Masonry light well
Build two walls perpendicular to the facade
The back wall is the existing facade
Waterproof mortar or coating on the exterior
Gravel bottom with drainage
Common mistakes
No drainage — The light well fills with water in heavy rain, water presses against the basement window
No grating — Leaves and debris fall in, causing blockages
Not sealed to the facade — Water runs along the facade into the basement
Too small — A tiny light well lets in little light and is hard to clean
