ODDO architects’ CH House redefines the traditional tube houses of Vietnam

There have been discussions on the lack of land for new constructions in urban cities, for a while now. While population increase, environmental problems, and social inequality have been considered the main reasons for this resource shortage, some argue that this concern stems from conspiracy, designed to cause inflation in the real estate bubble. However, irrespective of whether that is a fact or a myth, millions of people living in urban cities around the world—whether in developed countries or Third World countries—agree that there is a lack of space for life with basic amenities. The architectural approach for this problem, then, varies from city planning to spatial planning of tiny houses.
While urban planners extend solutions, in terms of land use strategies, building regulations and housing proposals, architects tend to focus on exploring possibilities of building amid unbuilt pockets of these highly dense cities. Developing countries, on the other hand, have dealt with constraints of space and social architecture for a long time. In Vietnam, this led to the construction of tube houses in cities, where the constraints of space translated into narrow houses placed adjacent to each other. At ODDO architects’ new project CH House, one gets a glimpse into how this architecture of narrow spaces was designed in Vietnam.

Built on the design principles of tube houses, CH House adapts to cater for modern needs and concerns. In a 4.2m wide and 35m long space—a width that is sometimes even considered small for a bedroom—the mixed-used building hosts a retail space and residence for a six-member family. The linear structure with five storeys of functional spaces, caters to the different needs of three generations under the same roof. Mimicking the typological distribution of a tube house, CH House too, hosts retail spaces on the ground floor and first floor and the residential spaces on the second floor.
Often, in houses with limited area, natural light, ventilation, and the opportunity to incorporate green spaces is comparatively challenging. At ODDO architects’ residential design, an interesting play of volumes helps tackle this issue. The architecture firm mentions that inspiration for this is derived from the traditional houses of Hanoi, which have spaces full of natural light and ventilation due to their inner courtyard design.
The lower two floors comprising the retail space draw on conventional grids, while the upper residential floors oscillate between levels, connected through steps. By breaking the linear continuity of the floor, different areas become separate modules with their own volume rather than becoming parts of a whole.
The stairs from the retail space on the first-floor lead to the common area with a kitchen and dining space. A wider stairwell allows the dining space to sit right under it, continuing to the top floor. Due to this planning strategy, the dining space is a multi-height space that lets in natural light from the skylight above and also incorporates a small green patch with an indoor tree.
The living room, situated on a higher platform from the kitchen, is connected by another set of stairs and segregates into two levels—stairs down to the bedroom and stairs up to a double-height recreational space with a huge tree that overlooks the exterior street. The third and fourth floor hosts multiple bedrooms in a similar play of levels, that elevates and lowers to create varying volumes and heights.
While all the functional spaces are connected through stairs, the staircase design varies in its characteristics and adapts to multiple functions. The staircase connecting the living room to the recreational spaces shapeshifts to form a vertical connection to the library with storage and seating, therefore, becoming a functional area rather than just an element of circulation. The staircases connecting the different floors also differ from each other in materiality and design, helping separate one part of the building from another and breaking the sense of dwelling in one long space.

In narrow buildings that are restricted horizontally and grow vertically, gardens and recreational spaces are normally placed on the rooftop. In CH House, a rooftop garden space is presented on the fourth floor with the recreational space on the second floor, becoming an integral part of the whole building. Primarily, the volume makes this space stand out, however, supporting it is the facade design.
Considering the climatic conditions of the region—which require natural light and ventilation—and the lack of sideway openings for the building, the front facade, the exterior elevation and the roof become the only planes to create openings. While the exterior part of the building opens to the narrow alleyways, the balconies are kept private to rooms adjacent to it, encouraging limited interaction with the neighbouring buildings.
With the need to establish a connection to the exteriors and simultaneously maintain enough privacy for its inhabitants, the front facade takes shape as an exterior skin that screens the building. It is designed as a double layer, with the outer layer made from perforated cement blocks and a steel-framed glass inner layer. Towards the interiors, these layers are accompanied by an additional green layer which provides cover from the sun and dust, allowing natural ventilation throughout the length of the house.
While concerns of ventilation and light were dealt with through the facade, skylights, fenestrations, and multi-height spaces, the other factor that the architects had to address was the need for greenery in a limited space. Though spatial configurations of the residence allow for indoor gardens and trees, incorporating them in the design naturally, without it appearing a forced presence amid the built structure was challenging.
Helping the design, in this aspect, is the material palette and the planning of spatial transitions. The trees, planters, and indoor gardens were placed in a manner that would mark passive edges between the different functions. A significant element of the interior design is the three void gap, separating the house’s volume—the light wells of the two main staircases and the recreational area near the front facade. These spaces, along with their role in delivering natural light to the lower-level spaces, carve out rooms for natural vegetation, breaking the monotonous flow of the built volumes. “CH house is not only a home for dwellers but also a place attempting to create the linkage between humans and nature that is very often missing in Hanoi because of its many environmental problems and limited green spaces,” mentions ODDO architects.
Though Vietnamese architecture reflects influences from many cultures and styles of different countries, the traditional presence of tube houses is an architectural and cultural identity completely owned by the Vietnamese. 21st century adaptations of tube houses by architects, explores this concept in a modern light. While ODDO architects created a front facade that is partially transparent, in most cases, this elevation remains open with balconies or movable screens.
Talking about their approach behind the design, ODDO architects share, “Family ties in traditional Vietnamese families are very strong. Usually, several generations live together under a single roof where many family events take place. In today’s world of modern technology, with smartphones and televisions, these ties have been weakened. The design of the space emphasises the connections among the family members, especially in the context of today’s hurried lifestyle in the new, economically growing Vietnam.”
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