The Casa Mac annexe is an open-air residential extension designed by Vietnamese studio CTA for an existing home in Phu My near Ho Chi Minh City. Conceived as a single, uninterrupted living space, the structure is sheltered beneath a sweeping canopy-like roof finished with scale-shaped bitumen shingles and split by a central skylight. Perforated metal screens suspended below the skylight soften natural light, while exposed brick walls, timber ceilings, and lush planting create an interior that blurs the boundary between architecture and the surrounding landscape.
Rather than following a conventional residential layout, the annexe integrates living, dining, and kitchen areas with a workspace, jacuzzi, koi pond, and vegetable gardens beneath one expansive roof. A compact block containing a restroom and bathroom is the only enclosed volume, while arched openings connect the extension to the main residence through thick brick walls. The Casa Mac annexe uses raw materials and open planning to encourage natural ventilation while creating a retreat that balances privacy, social gatherings, and everyday living.
Image Credit: Hiroyuki Oki
What's Driving This Trend
- Open-air Home Extensions
- Residential annexes with uninterrupted layouts reveal market potential for flexible living spaces that merge work, wellness, dining, and leisure without conventional room divisions.
- Canopy-led Architecture
- Sweeping roof forms with skylights and layered shading systems are reshaping how homes manage daylight, ventilation, and privacy in warm climates.
- Landscape-integrated Living
- Blended interiors with gardens, ponds, and raw natural materials point to new demand for homes that function as restorative retreats connected to nature.
Who This Affects Most
- Residential Architecture
- Design studios can differentiate through climate-responsive additions that expand homes while reducing reliance on enclosed, mechanically conditioned spaces.
- Building Materials
- Shingle systems, perforated metals, exposed brick, and timber finishes create opportunities for durable products tailored to open-air and semi-outdoor residential environments.
- Outdoor Living
- The fusion of kitchens, workspaces, jacuzzis, ponds, and gardens under one roof signals growth for integrated lifestyle products suited to year-round domestic use.
