Local Guides - Gilroy
How Much Does an ADU Cost in Gilroy?
If you’re pricing out an ADU in Gilroy, here’s the honest range: our 14 floor plans run from $199,000 to $599,000. That price builds in a permitting budget along with architectural plans, foundation, the factory-built home itself, crane delivery, utility hookups, appliances, and final inspections, with your exact permit costs confirmed for your address in the feasibility study. Across the full lineup, the numbers average out to around $395,000, though most homeowners building a comfortable one or two bedroom unit land somewhere in the $309,000 to $479,000 stretch.
We build every home in our Salinas factory, about 35 minutes from Gilroy, so a quick drive up the road gets you to a real finished unit you can walk through before you commit to anything.
On this page
A few representative models
| Model | Size | Layout | All-in price* |
|---|---|---|---|
| Four Fifty | 450 sq ft | Studio, 1 bath | $199,000 |
| Six Sixty 2BR | 660 sq ft | 2 bed, 1 bath | $339,000 |
| Seven Forty-Nine | 749 sq ft | 2 bed, 1 bath | $369,000 |
| Eight Eighty-Five 2BR | 885 sq ft | 2 bed, 1 bath | $399,000 |
| Nine Forty-Five 3/2 | 945 sq ft | 3 bed, 2 bath | $479,000 |
*Includes a permitting budget, not final permit costs. Permits and property-specific site work (septic, retaining walls, etc.) vary by property and are confirmed in your feasibility study.
That’s a slice of the roster. We have 14 models total, from a compact studio up through a 1,200 square foot three bedroom home, so there’s room to match the price to what you actually need.
What actually moves the number
Three things push a project up or down within that range, and none of them are a rate per square foot. First, size: more square footage means more materials, more factory labor, and a bigger foundation, so naturally it costs more. Second, bedroom and bathroom count: a second bathroom or a third bedroom adds plumbing, framing, and finish work that a studio doesn’t need. Third, finish level: the appliance package, cabinetry, and fixtures you choose shift the price inside a given floor plan.
Gilroy’s own zoning plays a role too. The city caps a detached ADU at 1,000 square feet, so our roomier three bedroom, 1,200 square foot models generally pencil out as attached additions rather than detached backyard homes here, sized against 50% of your main home’s floor area. Most Gilroy lots we hear from have plenty of room to work with something in the 450 to 945 square foot range as a standalone unit, which is exactly where our lineup is deepest. And if you keep the build under 750 square feet, you skip local impact fees entirely under state law; six of our models qualify. Larger units still only pay fees proportional to your primary home’s size, never a flat surprise charge.
We haven’t completed a build in Gilroy yet, but we’re actively working with homeowners there now, and the drive from our factory is short enough that site visits and inspections are easy to coordinate.
Getting an exact number for your lot
Every range above is a starting point, not a quote. The real number depends on your lot’s slope, soil, existing utility access, and how far the ADU sits from your panel and main lines. The fastest way to get specifics is our free Property Report, or the Online Property Analysis, which looks at your actual address and tells you what’s realistic before you spend anything. If you’re already deep into the numbers, our posts on ADU permits in Gilroy and ADU timeline in Gilroy round out the picture of what happens after you pick a model.
On financing: the $1,000 signup deposit is refundable if financing falls through. The feasibility study fee, $497 standard or $997 for an empty lot, credits toward your build and is refundable only if your property can’t host an ADU. Most homeowners use a HELOC, cash-out refinance, or construction loan against their home equity; we don’t lend directly. For a deeper look, see How to Finance an ADU in California, HELOC vs Construction Loan for an ADU, and ADU Loans California.
Frequently asked questions
What’s the cheapest ADU I can build in Gilroy?
Our Four Fifty is the lowest-priced model at $199,000 all-inclusive, a studio with one bathroom at 450 square feet. It’s a good fit if you want a simple, self-contained unit without extra bedrooms.
Does the price include permits and inspections?
Yes, in the sense that matters most: every model’s price builds in a permitting budget along with plans, foundation, the factory-built home, delivery, utility hookups, appliances, and inspections. Your exact permit costs are set by the city and confirmed in your feasibility study, and property-specific site work isn’t part of the listed model price, though we handle it in-house under your contract when a lot needs it.
Will I pay Gilroy impact fees on top of the build price?
If your ADU is under 750 square feet, state law waives local impact fees entirely. Six of our models qualify. At 750 square feet or larger, fees are proportional to your main home’s size rather than a flat add-on.
How do I find out what an ADU would actually cost on my specific lot?
Start with our free Property Report or the Online Property Analysis. Both look at your actual address and give you a realistic picture before you spend a dollar on plans.
Ready to see real numbers for your address? Contact us and we’ll walk through your lot, your budget, and which of our 14 models makes the most sense for your Gilroy backyard.
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More on building here: ADUs in Gilroy · Santa Clara County ADU regulations
