Four Metres Wide: Roof House Trades Floor Area for Terracotta Air

A four-metre-wide house now stands at the end of an alley in District 7, Ho Chi Minh City, where Trung Nguyen Architects has built Roof House for a young family with two children on a 77-square-metre site.

The Vietnamese studio's design gives up usable floor area on purpose. Every room opens onto a pocket garden or terrace, and a steep terracotta-tiled roof encloses high, sloping ceilings with exposed tiles and beams.

"The project is our exploration of a simple question, 'How much is enough to build?'" studio founder Nguyen Van Trung told Dezeen.

What does the house actually do?

The mechanism is straightforward. The studio preserved open voids around a compact, tightly organised volume instead of filling the plot edge to edge. Those voids carry the household's daily life outdoors.

"Our aim was to shift the focus from maximising floor area to maximising spatial quality. This led to a compact, tightly organised volume surrounded by voids that were deliberately preserved," Trung said.

"These voids are not treated as leftover areas, but as integral parts of the living environment. In particular, the garden creates a breathing space for the house, allowing family life to extend beyond the limits of the built volume," he added.

The entrance sits beside a perforated opening and leads into a yard-like garden that buffers the home from the street. Planting and a tree are wrapped by a terracotta-paved terrace. Sliding glass doors connect an eaves-sheltered sit-out to the living, dining and kitchen space, finished with stone floors and plaster walls.

A translucent sliding door separates the living space from a main bedroom at the back, keeping a direct route to the rear garden. The roof level drops lower over the kitchen and bedroom, while the taller volumes make the narrow rooms feel larger than their footprint.

How does one roof serve three floors?

Upper levels follow the same logic. A multi-purpose landing and the children's bedroom sit on the first floor; a studio and library occupy the second. Both levels overlook the front garden from small balconies, and a terrace with blue-painted steel steps links them.

Smaller sloping and gabled tiled roofs top each level, completing the home's stepped profile.

The sequence from alley to interior is deliberate. "The setback, garden and porch form an intermediate zone between the dwelling and the alley, creating an inhabitable depth between public and private space," Trung explained.

Flexibility comes from movable parts, not extra square metres. "Sliding partitions, level changes and variations in ceiling height allow this field to be reconfigured according to use and time. The architecture therefore supports multiple domestic scenarios without increasing the building footprint," he said.

What does this change for alleyway housing?

Roof House joins a growing body of Vietnamese architecture treating narrow urban plots as a design condition rather than a constraint. In Hanoi, ODDO Architects recently drew on alleyway spatial conditions for TH+ House, which features tall, narrow voids between rooms. In Kyoto, Tato Architects' House and Studio, another skinny home recently featured on Dezeen, animates a tight plot with skylit ceilings and zigzagging staircases.

For families on small alley sites, Roof House offers a workable template: build less, keep the voids, and let gardens and terraces do the work that extra floor area usually does.

The photography is by Hoang Le.