Blackened timber extension, Gosforth

They wanted an open-plan living space with more natural light and an inside/outside connection to take advantage of their large west facing rear garden. They also wanted to explore the possibility of a principal suite above.

MawsonKerr proposed replacing the existing poor-quality single-storey extension with a contemporary intervention that is striking in appearance but sympathetic in massing.

The composition reflects the roofline and pitch of the existing and allows for a lower eaves adjacent to the neighbour – interlocking the existing house without dominating it. Large openings to the ground and first floor bring the garden into the house, and a raised terrace allows a continuous connection between interior and exterior living areas. The whole extension is wrapped in blackened timber which is a bold but understated move.

The new extension significantly improves the thermal performance of the house, as the previous 1970s substandard extension was neither insulated nor airtight. The project is a great example of retrofitting an existing house. The extension in effect 'wraps' around part of the existing rear and side and provides a better performing fabric and efficient heating to make the living spaces comfortable to be in all year round.

The large panels of glazing are solar control glass which avoids overheating in summer afternoons and also gives a reflection of the trees opposite. Timber has been specified for both the frame and the cladding for its low embodied energy and thermal performance.

This high-quality contemporary design is an excellent example of what can be achieved within a conservation area without costing the earth.

Annual CO2 data was not provided