TL;DR
Placeholder summary. An above-garage ADU builds new living space over an existing detached garage, preserving the lot's footprint but requiring structural work to support the new floor.
Cost: $100,000 to $280,000Size: 400 to 800 sq ftTimeline: 7 to 12 monthsPermit complexity: High
Last verified: July 15, 2026
Placeholder content. Real above-garage ADU content will replace this in the next phase.
How Above-Garage ADU compares to the alternatives
Cost, size, timeline, and permit difficulty for all five ADU types side by side, with Above-Garage ADU highlighted. The right pick usually comes down to how much lot space and budget you actually have, not which one you like best.
| Feature | Detached ADU | Attached ADU | Garage Conversion | Junior ADU | Above-Garage ADUYou are here |
|---|---|---|---|---|---|
| Typical cost | $120,000 to $360,000 | $95,000 to $200,000 | $55,000 to $140,000 | $20,000 to $100,000 | $100,000 to $280,000 |
| Typical size | 400 to 1,200 sq ft | 400 to 800 sq ft | 300 to 650 sq ft | 150 to 500 sq ft | 400 to 800 sq ft |
| Typical timeline | 6 to 12 months | 5 to 10 months | 3 to 6 months | 2 to 5 months | 7 to 12 months |
| Permit complexity | Moderate | Moderate | Low | Low | High |
| Best for | Owners who want maximum privacy and a fully independent living space | Owners who want an ADU without giving up backyard space | Owners on a budget who already have an underused garage | Owners who want rental income fast at the lowest possible cost | Owners with a detached garage and little extra lot space to build on |
Other ADU types
See how the rest of your options stack up.