• A Design Guide for Basement Lightwells

    London Basement Lightwells

    Throughout our portfolio of basement conversions in Fulham and in Kensington we have explored the ways in which a lightwell can be incorporated into a basement extension to provide the maximum amount of daylight and views out.

    London Basement Conversions: Garden Lightwell

    The garden lightwell is the key lightwell in the design of basement extensions. It provides the functional requirement of light and air to the larger basement spaces and is a key feature of the basement extensions at ground floor at the garden elevation, where glass bridges and platforms link the large open kitchen dining spaces with the garden beyond. These functions and features can be configured in a number of ways and our various London basement conversions have explored a variety of solutions. The connection between the garden lightwell and the garden via a stair can be designed in a number of ways. Several of our Fulham basement conversions have incorporated a single flight of steps set alongside the garden wall and finished in robust and hard materials. A feature of this approach is the elongated views to be had from the basement interior up and along these steps. We have also incorporated timber and glass steps alongside the rear wall of the lightwell that connects to the glass bridge over. This approach forms a simple and elegant composition of glass platforms and balustrading with timber and steel supports. Our basement conversions in Fulham, in Ellerby Street for example, have been successful in specifying and detailing simple and elegant structures. A number of our basement conversions in London have also incorporated a series of store rooms giving off the basement and below the garden above. These rooms are either configured as a single large space or as two storage rooms with separate doors. Another of our Fulham basement conversions has incorporated a glass fronted study room linked to the main family room via a glazed corridor.

    London Basement Conversions: Street Lightwell

    Amongst our Fulham basement extensions we have explored a variety of designs for the front lightwell and the range of rooms that can be set off it. The front lightwell typically follows the profile of the bay window and the planning department produces detailed guidance on this. The top is enclosed with a steel grating lid with an openable section into which a steel ladder is fixed to allow escape from the lightwell and external access if required. In several of our Fulham basement conversions we have extended accommodation below the entrance path at the side of the lightwell and this has provided space for en-suite shower rooms. Other basement conversions have incorporated storage at the front edge of the lightwell. The walls of the lightwell are often rendered and painted. It is important to stop the render some 150mm above the ground finish above and expose several course of engineering brickwork to avoid water splashing against the render and unsightly staining occurring.

    London Basement Conversions: Mid Lightwell

    In several of our Fulham basement conversions we have incorporated a lightwell set in the middle of the basement against the party wall. This design approach provides a number of benefits. At basement level natural light and air is brought into the heart of the basement and accommodation such as study rooms can be located here. Set over a part of the width of the lightwell at ground floor is a link between the front reception room and the kitchen dining space. This link is filled with light with a rooflight over and window to the side. Often a structural glass panel is set into the floor to provide further light into the basement below. As Fulham architects we are always exploring ways in which natural light can be brought into the interior. Other of our basement extensions in Fulham have set either face of the lightwell at basement level with glass screens and doors to provide extensive views and access at basement level.

    London Basement Conversions: Interface with the Garden

    Basement extensions in London connect to a variety of garden types and sizes and it is a connection that is very important in relating a spacious kitchen dining space to the garden beyond. In addition to deciding upon whether the physical connection is a bridge or a platform there is a decision as to how the glass-to-garden interface is handled. Typically the interface is a series of steps, often at the full width of the garden, if the garden is set at a higher level than the finished floor or else an elegant drainage channel to collect the water run-off from the glass bridge if the garden and floor level are at the same levels. We have at several basement conversions in Fulham combined a glass bridge and steps that ‘break’ through a low level planter. This adds an interesting planted margin through and over which the garden can easily be seen.

    London Basement Conversions: Other Lightwells

    As London architects with a specialisation in basement conversions we have designed and built basement projects with a number of other types of lightwell to provide light and air to basement extensions. One of our basement conversions in London located in Adam and Eve Mews, Kensington had an existing lightwell at ground floor very much hidden away. Our project saw the opening up of the ground floor level to draw emphasis to this lightwell and then extend the lightwell into the basement and so provide a significant amount of daylight into the basement floor plan. A second Kensington basement conversion at Pembridge Mews, Kensington, incorporates a lightwell into the basement based on an existing small patio garden at ground floor level. A glass platform with several open sections allows the space to continue as patio space at ground floor whilst bringing light and air into the basement.

    London Basement Conversions: 3D Computer Visualisations

    Throughout our basement extension projects in London, as with all our projects, we use 3D computer visualisations to explore the building design at all stages of the design process. This is an excellent tool as it enables us to present clearly and easily readable images to our Clients and when asked to make adjustments it is an easy process. We are also able to model the passage of daylight through an internal space over the course of a day at a prescribed time and date. Again this is a very useful design tool and can be used for example in helping locate and size rooflights over a wrap around extension at the Ground Floor level of a basement project. Our Fulham basement extension in Ellerby Street used computer graphics to great effect in modelling the garden lightwell and helped in deciding upon the width of the glass bridge.