timber facade of Untiled House extension by Szczepaniak Astridge in London

Szczepaniak Astridge adds concrete and timber extension to London house

Untitled House is a residential extension and renovation in Camberwell, London, by architecture studio Szczepaniak Astridge that centres around a "concrete sculpture".

The project was undertaken by Szczepaniak Astridge for a client called Rachel, who is the VP creative of a major British fashion house.

Void above ground floor of Untiled House extension by Szczepaniak Astridge in London
Concrete forms the walls, ceilings and floors

Rachel asked Szczepaniak Astridge to create a home where she could relax and decompress after work.

"Untitled House has no name. Like a piece of art with no name," said the studio.

"We wanted to introduce a concrete-walled void through from the kitchen up to the bathroom. This enables smells and sounds to travel up and down the house."

Concrete bathroom, stone sink and Crittal screen of bathroom in Untiled House extension by Szczepaniak Astridge in London
The void reaches through the bathroom but has been enclosed behind protective glass doors

Concrete poured in situ forms the foundations, floors, walls and ceilings of the ground-storey kitchen and a new bathroom on the first floor.

A double-height space has been left open above part of the kitchen, connecting it to the bathroom above.

Concrete bath and Crittal screen in bathroom of Untiled House extension by Szczepaniak Astridge in London
Crittal screens separate the tub and the void

The gap is ringed by a concrete half-wall topped by polished stainless steel Crittal windows created by specialist metalworkers.

These windows form a screen for a monolithic bathtub that sits, like another miniature void, on the other side. The deep and square tub is formed of the same dark concrete as the walls and floor.

Stone sink in Untiled House extension by Szczepaniak Astridge in London
Stone sinks feature throughout

These sculptural concrete elements are a reference to the work of Gordon Matta-Clark, the architect-trained artist who made dramatic cut-outs in buildings.

"The bathroom on the first floor was designed as a place to retreat to, to guiltlessly linger and hang out," said the studio.

The kitchen is lit by skylights and the void

The sinks of dark polished stone were designed by Rachel and made to specification to complement the moody atmosphere of the room.

Downstairs, the kitchen is lit by light coming down through the void and by a long skylight cut into the timber-lined ceiling. A trough-style sink, salvaged and restored by the client, sits against a raw-concrete column.

Kitchen sink of Untiled House extension by Szczepaniak Astridge in London
A kitchen sink stands in a concrete niche

Grey concrete boxes form benches under both sides of the windowsills between the kitchen and outdoor terrace.

On the exterior side, deep timber eaves shelter the seating area and the bi-folding doors that open out on to the patio.

Skylight above dining table in Untiled House extension by Szczepaniak Astridge in London
Grey window boxes abut the window

This timber rear facade was designed Szczepaniak Astridge and built by Turner Prize-winning studio Assemble from birch plywood and solid beech with steel connectors.

"The design was conceived as a moving jewellery box," said Szczepaniak Astridge.

"The facade opens up and closes and is protected by a large 0.5-metre overhang from the rain."

Timber facade of Untiled House extension by Szczepaniak Astridge in London
The exterior has a large, timber-lined overhang

During the renovation process for the original house, the studio peeled back layers of wallpaper from the walls.

They used these discoveries to inform the palette of colours for the redecoration, and saved sections of the stripped paper for a book they made for Rachel about the project.

Szczepaniak Astridge is a London studio founded by Simon Astridge and Nicholas Szczepaniak. A previous project from the practice featured a rooftop extension with a timber bathtub in front of a window.

Photography is by Nicholas Worley.

More images

Void in Untiled House extension by Szczepaniak Astridge in London
Bathroom of Untiled House extension by Szczepaniak Astridge in London
Interiors of Untiled House extension by Szczepaniak Astridge in London
Kitchen sink and metal taps in Untiled House extension by Szczepaniak Astridge in London
Kitchen sink in Untiled House extension by Szczepaniak Astridge in London
Interiors of Untiled House extension by Szczepaniak Astridge in London
Interiors of Untiled House extension by Szczepaniak Astridge in London
Dining table in kitchen of Untiled House extension by Szczepaniak Astridge in London
Dining table in kitchen of Untiled House extension by Szczepaniak Astridge in London
Wood detail of Untiled House extension by Szczepaniak Astridge in London