Exposed rafters support a pitched roof incorporating a large skylight that allows daylight to flood into this rear extension added to a Victorian house in south London by local studio Grey Griffiths Architects.

The studio founded in 2016 by Tom Grey and Michael Griffiths was asked to oversee the renovation and extension of a terraced property in a conservation area in Clapham.

The one-bedroom garden flat featured a typical Victorian layout, with a series of rooms arranged off a corridor that extends along one side of the plan.

"The brief was to enlarge and reconfigure the property to achieve a second bedroom, create a bright open living area, and to add architectural interest to the space," said the architects.

An uninsulated bathroom at the rear of the house that was only accessible through the kitchen epitomised the neglected state of the interior and the need for extensive modernisation.

The property's location within the conservation area meant that an appeal was required to achieve planning permission, with the inspector ultimately agreeing that the proposal would enhance the rear of the house.

The shape of the new addition references the slanted roof of the existing closet return in the angles of its asymmetric profile.

The pitched roof also lowers the height of the eaves and therefore minimises its impact on the neighbours on either side.

Inside the extension, the vaulted roof form is highlighted by exposing the timber framework and suspending a series of industrial pendant lights from the rafters.

"The internal roof structure has been left open to increase the volume of the internal space," added Grey and Griffiths.

'The visible oak rafters add a warm, repetitive interest to the space and draw the eye up to the internal ridgeline, enhancing the feeling of space."

The extension now covers the full width of the building's rear facade, creating space for a lounge area and kitchen on either side of a partition spanning the space between two supporting pillars.

Large glass doors on either side of the brick pillar to the rear of the space provide a view out towards the garden and allow natural light to flood into the interior.

Timber that complements the roof structure is used to frame the doors, which can each pivot to open the whole room up to the outdoors.

To enhance the bright and open feel requested by the client, a long east-facing roof light is incorporated into the ceiling above the kitchen.

A new bathroom is positioned off a central transitional space between the two bedrooms to the front of the house and the kitchen and living space.

Oak rafters are also left visible in the bathroom, where a skylight above the shower and a window looking onto an internal courtyard draw daylight into the room.

The courtyard can be reached from one of the bedrooms. Another window looking onto this outdoor space allows light to filter into the transitional area, which is designed for reading and accommodates a stove and storage.

Photography is by Adam Scott.