Permit guides

ADU Permits in San Bruno: a Homeowner's Guide

San Bruno pairs a detailed ADU checklist with design guidelines that shape what your unit can look like.

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

Who handles your permit

ADU permits in San Bruno run through the Community & Economic Development Department, split between its Planning Division and Building Division. The city publishes a dedicated ADU Submittal Checklist that walks through every sheet reviewers expect. One local touch: the building official assigns a brand-new address to the ADU itself.

What you can build

1,200 sq ftMax for a detached ADU under state law

New addressThe building official assigns a separate address to the ADU

Daylight planeMultistory projects must address daylight plane or façade articulation

7am – 10pmConstruction hours, Monday through Saturday

4 ftMinimum side and rear setbacks for detached ADUs

60 daysState deadline for the city to act on a complete application

Design guidelines matter here

San Bruno's Residential Design Guidelines aren't just suggestions — multistory ADU projects need to show how the upper floor conforms to either the daylight plane or façade articulation options, with the treatment explained on the plans. Elevations are required for all sides of the building, including sides with no proposed changes, and must label siding, roofing, trim, windows, doors, and finishes.

What goes into the submittal

The city's ADU checklist is thorough. Beyond the standard site plan and floor plans, expect to show:

Main electrical panel size and location, including subpanels; water heating system type and location; HVAC equipment and plumbing fixture locations
Gas pipe schematic (may be deferred) and prefabricated roof truss calculations, stamped by the truss designer (may be deferred)
Construction Best Management Practices imprinted on the plans, plus the city's construction noise note (85 dB max, 7am–10pm Mon–Sat)
Landscape plan with plant schedule (Latin and common names, sizes, quantities); heritage tree removals need a separate permit

Budget for separate permits. San Bruno requires separate plans and permits for work in the public right-of-way, automatic fire sprinklers and alarms, structure demolition, and any revisions to the approved plan. These aren't included in the ADU building permit.

Where applications usually get stuck

Design guideline compliance. Daylight-plane and articulation requirements generate the most design-side corrections.
The separate-permit stack. Sprinklers, demolition, and encroachment each have their own review — applicants who discover them late lose weeks.
Heritage trees. Removal needs its own permit under a separate code section; don't assume it's covered by the ADU approval.

Not sure where to start? That's the part we do. We check your property against the requirements, coordinate the plans and specialists, and manage the submittal and corrections — one point of contact.

Tell us what you need help with.

Not sure where to start? That's what we're here for.

Send your project

Erik — (916) 540-8960 · Vall — (916) 956-8106
office@pcg-engineering.pro