The project updates the original organisation of the site, which featured a building to the north and one to the south that each opened onto a large courtyard typical of homes in the area.
Arch Studio retained and restored these two original structures while introducing a wooden volume that connects them across the site, forming a spacious holiday home for its owner.
Topped with a wave-like roof and filled with new living areas, this wooden volume also splits the existing courtyard into a series of smaller external spaces.
"The original spatial pattern featuring one front yard and one back yard is reorganised to form six yards with different scales, landscapes and functions," explained the studio.
"The insertion of the new wooden construction strengthens the undulating layering of the existing roofs, and creates a dialogue between the old and new building volumes."
Mixed House's interior blends together both new and old spaces, with a living room opening onto two small yards at the front, a dining room at the centre, and bedrooms on either side of a secondary living room at the rear.
Materials have been left exposed to highlight the combination of new, restored and old, captured in the layered views through the home from the courtyards.
The timber frame of the extension mirrors the traditional construction of the existing roofs, and new brick walls have been constructed using recycled red and grey bricks that echo the original buildings.
"The newly built wooden construction adopts cedar plywood as a main material and applies traditional beam-lifted frames, to echo the features of traditional northern Chinese houses," explained Arch Studio.
"[This] continues the existing old house's wooden frame with new structural extensions, creating a dialogue between the old and the new," it continued.
Each of the small yards throughout Mixed House has been given a distinct character and scale through landscaping and planting, including a thin bamboo path alongside the entrance and a courtyard with a maple tree at the home's centre.
Windows and sliding doors framed in laminated bamboo allow the living spaces to be opened to these yards, while beneath the new roof clerestory glazing helps draw in additional natural light.
To emphasise the feeling of continuity between Mixed House's interior living spaces and the external yards, both have been finished with red and grey paving.
Arch Studio took a similar approach to Mixed House in another recent restoration project in Beijing, which involved connecting a series of brick and concrete structures with a network of rooftop walkways.
Elsewhere, in northern Beijing MDDM Studio recently used yellow paint and terrazzo fixtures to brighten up an apartment.
The photography is by Jin Weiqi.
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