Fuelled with the desire to make their grandchildren experience the best days of childhood making leaf huts, running in the woods, or simply daydreaming, an elderly couple commissioned Ho Chi Minh City-based studio H2 to create a retreat on the shores of Da Bang Lake in southeast Vietnam. 'Tree House by the Lake' lies within a perennial conch forest amid corn fields and rubber gardens visible in the distance. The two-storied residential architecture is built from local scrap materials, and weaves in the existing trees of its place in the structural grid. Designed as a living built form, in harmony with the natural landscape that engulfs it, the house is defined by a whimsical play of apertures, materials, planes, and pathways.

The two storeys are distinctly contrasting in nature: the lower floor is transparent, light, and takes up less available ground space for domestic utilities, whereas the upper one is closed off, weighty in appearance, and spans a large interior footprint dedicated to the family living. Pivot glass doors sweep in and out of the ground floor, the space peppered with tree trunks. The circulation is undisturbed by these natural sculptures that appear not only around the cane and timber seating but are also encased centrally around a winding metal staircase. The interiors open out to the garden outside, becoming one with the rustic landscape. The polished concrete floor makes way for a vast pebble garden located adjacent to the lake.

While a glazed skin wraps the lower floor, the introverted upper floor has corrugated metal walls in a weathered finish. A large elliptical opening centrally punctures its façade, framing views of the immediate garden and lake, and the distant rice and corn fields. Structured around a metal grid composed of thin bars, the projected window sill double as seating for children where they can sit cross-legged immersed in a book, or a curious conversation. A linear hallway with wooden flooring ties two bedrooms on opposite ends of the floor. The rooms have weathered iron walls and large terraces with wide views of the surroundings. The hallway is designed keeping in mind the children remain in close contact with nature even while they are indoors, and that the land, sky, and water never seem far from one’s sight. Several voids carved within the space let in air and sunlight: from skylight sweeping above the hallway to circular fenestrations, and empty spaces taken over by elements such as netting for play, winding tree trunks, and potted plants. From above, if one looks at the floor below, it appears as if a grey carpet is spread for a picnic in the garden: the scenery, seemingly transient in nature, aptly conveys the ecological approach of the project.

“The project was brought up from the ground by us, relying on the big mother-of-pearl trees, from the use of old "scrap" materials to make the building look like it has been there for a long time,” says the design team at H2. Repurposed metal sheets, glass, and wood have been sourced from old houses from nearby sites as well as from the scrap market. The idea was to reduce building costs as well as to lessen the impact of the built form on the environment. “The building has an idyllic, old-fashioned appearance of the colour of materials that have been tinged with time. But at the same time, it still retains the essential features of a building, which are comfort, necessary privacy, flexibility, and invitation.”

The oversailing upper storey shelters below the quaint family quarter and a pebbled garden dotted by a hammock, and furniture for informal seating. A certain industrial essence permeates through the built form: in the use of unfinished walls and furniture, the fluid and undistinctive transition between different spaces, and vast landscapes to tinker with things.

Adding to the crop of contemporary Vietnamese architecture where vernacular materials and ecological techniques are increasingly being deployed in building construction, Tree House by the Lake too is rendered as a modest interpretation of the place it sits on. Previous projects from Vietnam published on STIR include H&P Architects’ climate resilient floating house for the flood-ravaged Mekong Delta, an office space in Ho Chi Minh City wrapped in a biophilic façade by VTN Architects, a residential edifice of glass, concrete and vines (the Labri House) in the city of Huế by Nguyen Khai Architects & Associates.