Extension to Georgian House by Henning Stummel Architects

January 20, 2010

In order to to restore the original layout to a Georgian townhouse in central London, Henning Stummel Architects designed an extension that placed all the bathroom facilities into their own structure tacked on to the house and accessed via extending the openings to the existing
fireplaces on the first three levels.

Full description after the photos….

Extension to Georgian House by Henning Stummel Architects

This is a timber extension to a Georgian townhouse. The house is a typical example of a defined typology, so we wanted to differentiate old and new in line with the recommendations of the ‘Society for Protection of Ancient Buildings’. We also wanted to keep this intervention reversible, i.e. the extension could be removed again. There is a long tradition of timber extension to Georgian buildings.

From a practical point of view, space was extremely limited and all materials had to be brought in through the front door. Timber offered a compact wall build up, with good thermal insulation and a dry construction. Carpenters could perform most of the building work, limiting confusion between trades. Finally the material also fulfilled the conservation area requirement demanding the use of traditional materials that require craftsmanship.

The fenestration was to be in ‘keeping’ with the neighbourhood. Our response was to propose a building without windows. Sanded Perspex boards blend seamlessly into the ship lapped surface and give the impression of a homogenously clad timber box. During the daytime the Perspex appears to be grey and we played with this, choosing to paint each board in a different shade of grey to further conceal the location of ‘windows’. The colours were carefully chosen to create a dialogue between new and old.

Consistent with the camouflage idea the openings were to be distributed randomly. Plywood sheathing on the studwork inside and out, gave rigidity to our wall, which allowed us to randomly scatter horizontal slots across the façade. The ply acts like a stress skin, and the loading is taken on detours on its way down.

Internally this extension offers two bathrooms and a toilet/utility room. These rooms are not permanently habitable and don’t require conventional windows. The rooms have discreet trickle ventilation and mechanical extracts.

Clearly with three bathrooms stacked one an top of each other the services are complex and these are accommodated within a 150mm full width service duct through all floors parallel to the party wall. This accommodates the rainwater down pipe, water, sewerage, wiring, toilet cisterns, vanity cabinets and mechanical ventilation. Consequently the two fenestrated facades could be left free from any installations. Being inside these rooms looking out is reminiscent of being inside a lantern.

These rooms are wet rooms and a water resistant wall finish had to be specified. We chose an opaque but translucent white Perspex. The walls are entirely covered, eliminating all ledges that would have collected damp or dust. The Perspex is silicon mounted on the white painted, ply. The walls appear brilliant white and the translucency reveals the random pattern of the horizontal window strips, creating serene space of contemplation.

Visit the website of Henning Stummel Architects – here.