Basement Lightwells

Much of the success of our portfolio of basement extension projects has been derived from the design of the basement lightwell.  Here the lightwell links the basement to the garden and fills the largest basement room with natural light and provides natural ventilation.  The basement lightwell is also an opportunity to use glass in a variety of ways, from stair balustrading to a glass bridge over the lightwell connecting the kitchen to the garden.

This describes the rear garden lightwell.  There are also lightwells to the front of the property and to the middle of the basement extension.  The front lightwell is typically a simpler affair as the planning department have quite a prescribed view of what it should look like, given that this lightwell is an indication of the basement extension to the passer-by.  The lightwell is enclosed with a steel grating over it set in the same plane as the garden paving.  Often a section of the grating is openable and below this is a steel ladder for escape purposes.

At basement level the lightwell whilst smaller than that to the rear of the property, still provides natural light and ventilation to the room giving onto it.  The middle lightwell can have a big impact on a basement extension and create some interesting spaces bringing light and natural ventilation into what might otherwise be the less well naturally lit part of the basement.  We have also used a rooflight over a space with a structural glass floor below to similar effect in bringing light into the basement room and providing views of the sky from within the basement.

The key to success is the use of natural light combined with the transparent and reflective qualities of glass.  These issues are best explored in the design stage with the use of 3D computer graphics where a sense of how the space works can be explored with a variety of designs.

A lightwell is the means by which natural light and ventilation is brought into a basement extension.  They are typically to the rear and front of the basement and sometimes in the middle of the space.  The front lightwell is typically smaller and may have more planning restrictions set upon it than the lightwell to the rear.  The rear lightwell also typically provides access via steps to the garden and is the main source of light and ventilation to a large family room.

The majority of garden light wells have stairs connecting the lightwell to the garden above.  These are often at the boundary wall to the side of the lightwell.  We have also designed these stairs so that they connect to a bridge over and this can work very well when the bridge is in glass and so is the stair balustrade.

The glass platform over  a basement lightwell to the garden side provides access from the ground floor, typically the kitchen and dining room out into the garden.  These platforms are often patterned so as not to be clear glass and have an anti-slip finish.  A section at he outer edges is often left open to maintain a flow of air to the basement lightwell.