In Lit-et-Mixe, in the Landes department on the French Atlantic coast, Parisian architect Maud Caubet has completed an extension to a house built in 2018. On a 1,510 m² plot, she added an additional 48 m² volume to the existing building (130 m²). The two buildings now form an ensemble that can be extended in a modular fashion.
The design follows the idea of a house in harmony with its surroundings. The construction stands on concrete supports, which largely preserves the natural ground. The dark wooden façade – finished in saturated Scots pine – blends in with the vertical structure of the pine forests. The choice of materials and colors is based on the natural surroundings.
Access to the roof terrace is via a central concrete staircase. From here, the view opens up to the nearby Atlantic coast.
The construction consists of prefabricated timber frame walls with wood fiber insulation. A local carpenter realized the building using element construction, which enabled short assembly times and minimal intervention in the terrain. Exposed concrete and a green roof were also used. The space under the house remains open for use – for example as a storage area or a shady place to spend time in the summer. A succinctly integrated pool is located under the second structure.
The residential building now consists of two connected structures. The western volume contains the living and dining area, kitchen, garage and two bedrooms. The south-facing terrace is protected by a roof overhang. The new, smaller volume to the east forms an autonomous unit with bedroom, bathroom, dressing room and office. Both “cabins” are connected by a covered external corridor.
The modular structure can be extended – further structures have already been included in the design. This means that the building remains adaptable for future forms of living.
The interior design focuses on natural colors and a clear room structure. Shades of green, blue tones and the brown of the tree bark reflect the colors of the forest. Wood paneling and large windows create a close connection between the interior and nature. The two buildings meet in the central patio, where the boundaries between inside and outside become particularly blurred.
The project meets the requirements of the French energy efficiency directive RT2012. The construction is based on a base of exposed concrete with a timber structure on top. The timber walls (145 × 45 mm, class 2 treated) are insulated with rock wool (145 mm plus 50 mm inner layer). The roof has a double layer of glass wool insulation with a total thickness of 420 mm. The floor slab consists of hollow core slabs (16+5).
The building is heated via a radiant underfloor heating system (Deleage). A thermodynamic water heater (270 l, Aeromax 3) completes the energy system. Windows and doors are made of thermally broken aluminum with double glazing (4/16/4, Low-E).
With the house in Lit-et-Mixe, Maud Caubet has set an example of modular residential architecture in a sensitive landscape. The design responds to the site conditions, enables future extensions and creates a retreat that blends into the natural environment through the choice of materials and building structure.
Also interesting: The hut in the forest by PAN tretopphytter in Norway.












