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Permit guides

ADU Permits in Saratoga: a Homeowner's Guide

What you can build, which permits you need, and how Saratoga’s site-heavy review actually works — in plain language.

Last updated October 2026. Rules change; always confirm current requirements with the city or county before you build.

Who handles your permit

Saratoga’s ADU permits run through the Community Development Department, 13777 Fruitvale Avenue, Saratoga, CA 95070. Building: (408) 868-1201; main department line: (408) 868-1222. The public counter is open Monday–Thursday, 8:00 am–12:00 pm and 1:00 pm–5:00 pm — closed every Friday, so don’t plan a last-minute Friday drop-off. Submittals don’t require an appointment, but incomplete plans are not accepted.

What you can build

Saratoga reviews ADUs ministerially under state law, with local standards aligned by City Ordinance No. 376 (adopted October 2020):

There is no minimum lot size for an ADU under state law. Converted garages and other existing structures keep their current footprint — no new setbacks apply to the conversion itself.

No plan library — a deposit-driven review instead

Saratoga doesn’t publish a preapproved ADU plan library. What’s distinctive is the depth of site review and deposit-based specialist reviews: arborist and geotechnical reviews each require a deposit agreement with the application, which the city draws against for staff and consultant time. Tree protection is a real gate — an arborist report is required if work is proposed within five feet of a protected tree’s canopy dripline, including neighbors’ trees — and WUI-area properties face a separate fire conformance checklist. Boundary surveys are required within two feet of a setback; topographic surveys within one foot of max height or on 10%+ slopes.

What goes into the submittal

• Application form signed by the property owner, letter of authorization if an agent is acting, and a preliminary title report dated within six months.
• Plot/site plan as the first sheet — all structures, measurements to property lines, easements, setbacks; most site plans must be signed or stamped by a California licensed land surveyor.
• Foundation plan, floor plan, exterior elevations, detailed structural sections, plus structural calculations.
• Title 24 energy compliance forms printed or sticky-backed on the plans.
• Grading and drainage plan; tree protection plan and arborist report (plus deposit agreement) where applicable; geotechnical report where applicable; WUI fire conformance checklist, stormwater forms, and WELO landscape calculations where applicable.
• Materials and color board, photos of all sides of existing structures, and neighbor notification forms.

Where applications usually get stuck

• Trees. Arborist review, tree protection, and the deposit add a review cycle flat suburban cities don’t have — and neighbors’ trees count.
• WUI conformance. Hillside and interface-zone properties face fire-material requirements that standard plans don’t satisfy alone.
• Survey triggers. The boundary and topographic thresholds are narrow — within 2 feet of a setback, within 1 foot of max height, slope at 10% — and tight lots land right on them.
• Slope math on the cover sheet. Average slope must be shown per the city’s formula, computed from a topographic survey — surveyors know it, DIY plans usually don’t.
• Friday closure. With the counter closed Fridays, questions and resubmittals queue into the next week.