A late-1970s timber house on a hillside in Hayama, Kanagawa, is now a home and studio. Architect Anna Naganuma and designer Shohei Hasegawa of HYAN kept the wooden frame and rebuilt the rooms around it.
Green sandwich house: keeping the frame
The home renovation known as Green Sandwich House began with a decision not to demolish. The house predates 1981 and was built under the seismic code of its era. The team kept the undamaged timber columns and beams and added seismic reinforcements.
Keeping an older Japanese building while updating its character has a close parallel in Shizunoyu Fukushima’s 1983 Bathhouse Revival With Curved Design, where new forms and vibrant tiles bring an older structure back to life.
A living room that links every zone
Studio HYAN organized the ground floor around a central double-height living room. From this room, the kitchen, pantry, study and garden are all within view and reach.
A new space called a doma sits off the living room. A doma is a traditionally earthen-floored area in Japanese houses, used as an entry or work space. Here, the team carved it out of a former tatami room. They removed the matting, changed the floor elevation and folded in a former closet nook.
The doma serves as a flexible threshold. Residents can work there, host guests or simply sit and relax.
Dividing space without walls
The plan avoids solid partitions. Instead, changes in floor level signal where one function ends and another begins. Sightlines, shifts in material and textiles that can be moved also help define each area.
Textile artist Haruka Shoji designed the custom curtains. They frame the large openings and the doma, and they soften the daylight and garden views as the hours pass.
Terrazzo against aged timber
Terrazzo is a composite of stone chips set in cement and ground smooth once it cures. The team hand-ground the terrazzo on site for the kitchen countertops and the washbasin.
For another take on the stone-chip surface used on these counters, see HIMACS Terrazzo With High Recycled Content, a contemporary terrazzo that shows how the material has evolved since traditional hand-ground methods.
These new surfaces meet the old frame directly. The terrazzo creates a tactile contrast with the exposed, aged timber, so each material stays legible beside the other.
The project’s photographs were taken by ©Katsuhiro Aoki, who documented how the restored frame and new surfaces sit together. The result shows that a home and studio can share one building. The Hayama house keeps its original structure and gains a new way of living inside it.
H/T designboom.com
Frequently asked questions
What is a doma in a Japanese house?
A doma is a traditionally earthen-floored area in Japanese houses, used as an entry or work space. In the Green Sandwich House, the team carved a new doma out of a former tatami room off the living room.
Did the Green Sandwich House renovation keep the original timber frame?
Yes, the renovation began with a decision not to demolish the house, and the team kept the undamaged timber columns and beams. They also added seismic reinforcements to the existing frame.
How were the terrazzo kitchen countertops made in the Hayama house?
The team hand-ground the terrazzo on site for the kitchen countertops and the washbasin. Terrazzo is a composite of stone chips set in cement and ground smooth once it cures.
How does the Green Sandwich House divide space without walls?
The plan avoids solid partitions and instead uses changes in floor level to signal where one function ends and another begins. Sightlines, shifts in material, and movable textiles such as custom curtains also help define each area.
More in
Architecture
All Architecture
More like this
Herzog & De Meuron Transforms Iconic Midcentury Warehouse into Eames Institute of Infinite Curiosity
ToB.Studio's Timber Bike Station Offers Sustainable Cycling Amenities Along Germany's D9 Route
Megowan Architectural Crafts Seamless Indoor-Outdoor Flow with Panoramic Bay Views in Mount Eliza
Sora Villa in Bali Transforms Two-bedroom Living with Recycled Ulin Hardwood and Zen Design
Hilltop Cottage: A Timber-Clad Retreat Overlooking New Brunswick's Scenic River Valley
