A second home inside the one you own
An attached ADU turns existing square footage — a basement, the space above a garage, or a side addition — into a self-contained suite with its own entrance, kitchen, and bath. Because the foundation and structure already exist, it's the lowest-cost ADU type we build: $85,000–$180,000 for 300–700 sq ft, with a 4–6 month construction phase.
Built for family first
Most of our attached-ADU clients are building for people, not tenants: aging parents who need independence without distance, or an adult child moving home. The design work reflects that — separate entrances, sound insulation between units, and accessible layouts where they're needed. Planning for parents? Read our guide to multi-generational ADUs.
What the basement scope covers
Basements carry their own requirements and we design to them from day one: waterproofing, egress windows and fire-safety separation, sound insulation, and MEP with separate-meter options so the unit can be rented cleanly later. The contract runs through final inspection and certificate of occupancy.