ADU vs Addition vs Garage Conversion
Three ways to add living space to your property — compared by 2026 build cost, rental potential, value added, and timeline.
Cheapest path to extra space
$0
starting cost — garage conversion
Typical all-in build cost range (2026)
Bars show the low-to-high cost band for each option, scaled to the same axis.
| Factor | 🏡 Detached ADU | 🧱 Home Addition | 🚗 Garage Conversion |
|---|---|---|---|
| Typical cost | $150,000–$350,000 | $80,000–$200,000 | $60,000–$130,000 |
| Separate rentable unit? | Yes — full separate unit | Rarely — usually no separate entrance | Often — can be a JADU/ADU |
| Home value added | Highest | Medium–High | Medium |
| Typical timeline | 6–12 months | 4–8 months | 2–5 months |
| What it is | A standalone dwelling with its own kitchen, bath, and entrance. | Extra square footage bolted onto the existing house (bedroom, suite, etc.). | Converting an existing garage into livable space — cheapest path to a unit. |
💰 Finance whichever path you choose.
ADU, addition, or garage conversion — most homeowners fund the build with home equity or a renovation loan. See what you could qualify for; checking rates won't affect your credit score.
Data & method: Detached-ADU figures use ADUCosts 2026 build-cost data. Home-addition and garage-conversion ranges are market-typical national estimates (design + permits + construction; excludes land).
Disclaimer: Costs, rental eligibility, and value added vary widely by location, size, finishes, and local zoning (e.g. whether a garage conversion qualifies as an ADU/JADU). These are estimates for general guidance — not a quote or financial advice. Confirm with local builders and your jurisdiction.
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