Downton Avenue is a sustainable adaptation of an Edwardian home in London.

Downton Avenue is a sustainable house extension in London which extends and renovates the ground floor with a stepped extension and extends the roof space with a dormer. The sustainable house extension design references the Edwardian details of the local area with an arched projecting window seat and textured brickwork.  

The sustainable house extension is built in timber frame and reclaimed Suffolk white brick which is sourced within 50 miles of the site. It also uses wood fibre insulation which has net positive embodied carbon.

Inside a new oak stair is inspired by the original features and sliding pocket doors are used to make the most of the space.

As part of the works for the sustainable house extension we are improving the energy performance of the original house, adding insulation beneath existing floors and upgrading the performance of the existing glazing.


The project was featured in the RIBA exhibition ‘Long Life, Low Energy: Designing for a circular economy’ which you can read more about in our news page highlighting the RIBA’s RIBA’s Built for the Environment report. We also wrote about the project's embodied carbon benefits in Design for Me article: Making more with less about sustainable house extensions.