Small Glass Extension to Listed Building in London

IQ Glass designed and installed a small glass box extension to this Grade II listed terraced home in South London. The glass box extension was designed to fit along a long narrow plot in the garden, ensuring access to the lower ground floor wasn’t affected whilst expanding the living space on the upper ground level. 

The fully glazed extension included high specification elements of structural glass supported with slim steel sections. Along the side, sliding minimal windows were used to grant direct access to the small garden area.

In small extensions, the amount of glass to frame appearance is important. The slim 21mm framing of the sliding glass doors meant that the maximum amount of glass could be used along the relatively small elevation, with little interruption to the light or views. 

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Camberwell, London

Surrounding the sliding glass doors was a slim steel supporting section which was specified with back painted glass for a smooth, sleek appearance. Internally, aluminium pressings were powder coated to the same colour as the sliding door frame, creating a coherent finish.

The steel sections used internally on the glass box extension support the structural glass roof, maintaining a minimal design to compliment the traditional exterior design. 

Further back into the extension a fixed, frameless picture window allows the light to stretch further through the long narrow space, the shape required to maintain access to the basement rooms. This large, floor to ceiling window provides side entering light into the extension and allows a view out onto a small seating area.

The highly glazed extension was carefully designed to create a contrast against the listed building, with the backpainted glass used to contrast the traditional brick of the terraced home. When extending or renovating a listed building, particular attention must be shown to the fixing details. 


IQ will always ensure the structure we are fixing to is solid to ensure any original brick or stone is not going to crumble when glazing systems are fixed to it. For this small glass extension, the original brick of the listed building was strong enough to accommodate the new extension.

To talk to a member of the technical team about a listed building project, email us at