ADU Permitting Differs in Every Marin City. Here Are Seven Free Guides

Marin Builders Association member Burton Builders LLC has published a free set of city-by-city ADU permitting guides covering seven Marin municipalities. The guides are written for homeowners and for the trades who work alongside them, and they are free to read with no sign-up.

State ADU law sets the floor, but the day-to-day experience of getting an ADU approved still varies a lot from one Marin city to the next — different height limits, different fee schedules, different rules once a lot is on a hillside or in a fire severity zone, and different turnaround at the counter. A homeowner in Ross and a homeowner in Novato are working through genuinely different processes. Most of the confusion we see on first calls traces back to that gap.

Each guide covers the same ground for its city:

• Size and height limits for detached ADUs, attached ADUs, and conversions
• Setbacks, parking rules, and owner-occupancy requirements
• Where the fees actually land, including school and impact fees
• Hillside, flood, and wildfire-zone requirements that change the scope
• What the review path looks like, and the state timelines that apply
• Direct links to each city's own ADU page and planning contacts

The seven Marin ADU guides:

• San Rafael
• San Anselmo
• Mill Valley
• Novato
• Larkspur
• Tiburon
• Ross

The guides are built on work Burton Builders has permitted and completed in the county. We have built over a dozen ADUs in Marin — detached cottages, garage conversions, and backyard studios in San Rafael, San Anselmo, Mill Valley, Novato, and Fairfax — alongside remodels and additions. A selection of those projects, with photos, is collected at burtonbuildersllc.com/portfolio/county/marin.

We re-check every guide against the current ordinance and fee schedule, and each one lists the city and state sources it draws from so readers can verify anything themselves. If you spot something out of date in your city, we would genuinely like to hear about it.