How Long Does an ADU Take in Gilroy? A 2026 Week-by-Week Timeline

A factory-built ADU in Gilroy typically takes about 4.5 to 8 months from first call to move-in, and Gilroy owns the fastest permit lane in our service area: with a pre-approved plan set and complete documents, the city can issue ADU permits in about 15 working days. Custom plans follow the standard 60-day ministerial clock. Site conditions and utilities can still add time, and review pace stays in the city’s hands, so week counts below are a plan, not a promise.

The short version: Weeks 1 to 2 confirm your lot and the 1,000 square foot detached cap. Weeks 3 to 8 design and prepare documents. Permit review runs about 15 working days on the pre-approved path or up to 60 days custom, while your home is built in our factory 35 minutes away. The last act is one crane morning, utility hookups, and the final inspection.

The Gilroy ADU timeline, week by week

Weeks	Phase	What happens
1 to 2	Property analysis	Free 30-minute review: setbacks, transit distance, size cap check
2 to 4	Site visit + feasibility study	Free site visit, then the feasibility study sets the exact quote and parking placement (front setback and driveway allowed)
4 to 8	Design + plans	Model locked under the 1,000 sq ft cap, site plan, Title 24
8 to 14+	Permit review	About 15 working days with pre-approved plans and complete documents; up to 60 days custom
9 to 18	Factory build + foundation	Parallel with permitting
Final week	Delivery + finish	Crane set in one day, hookups, final inspection, keys

The bottom line: about 4.5 months for a small model on the fast lane, roughly 8 at the larger end. Building the same ADU on site typically takes 16 to 24 months.

What moves the schedule in Gilroy

Which permit lane you qualify for. Gilroy pre-approves standardized construction plans, and that lane is where the roughly 15 working day permits live. Complete documents are the ticket; one missing sheet moves you to the back of the queue. The full local rulebook, including the 1,000 square foot detached cap and height rules, is in our Gilroy ADU permits guide.

The size cap simplifies design. With detached units capped at 1,000 square feet, the model conversation is shorter: twelve of our 14 homes fit, including every 945 square foot configuration. Fewer design iterations, faster lock.

The deed restriction is paperwork, not delay. Before issuance the city records a restriction against rentals under 30 days. It is routine and we prepare it with the application.

The parallel build

While Gilroy processes your permit, your home is being assembled about 97% complete in our Salinas factory, roughly 35 minutes away on Highway 101. The foundation is formed and poured in the same window. On delivery day the home arrives essentially finished: one crane set, then utility hookups and the final inspection.

Your model pick writes the last number: the 450 square foot studio at $199,000 leads at about 4.5 months on the fast lane; the 660 square foot Six Sixty 2BR at $339,000 is the rental workhorse; the 945 square foot three-bedroom, two-bath at $479,000 is the biggest home the cap allows, each priced with a permitting budget built in. For the income math on Gilroy’s long-term rental market, start with how much rent an ADU can earn.

Frequently asked questions

How fast can a Gilroy ADU permit really be issued?

About 15 working days with a pre-approved plan set and complete documents, per the city. Custom designs follow the standard 60-day ministerial clock from a complete application. Workload can stretch either lane; nobody controls that part.

Does the 1,000 square foot cap slow anything down?

If anything it speeds decisions: the model menu is clear and the city’s standards are objective. It only matters if you wanted a 1,200 square foot home, in which case a neighboring jurisdiction or a 945 square foot three-bedroom is the conversation.

What runs in parallel while the city reviews?

The factory build and your site’s foundation work. That overlap, plus Gilroy’s fast lane, makes this one of the quickest end-to-end ADU markets we serve.

What usually delays Gilroy projects?

Incomplete document packages and utility connection scoping. Both are preventable, and both are exactly what the feasibility study pins down before you commit.

Check your lane, free

Fast lane or standard lane comes down to your plans and your parcel. Book a free property analysis and our team will check your setbacks, transit distance, and model fit before you spend a dollar. About half an hour, no charge.