99 ADU builders filed 111 ADU permits on homes in unincorporated Marin County from October 2023 to September 2026; 37 filed one in the last 12 months. The middle filed job value was $205,000. The finished share isn't shown for ADU permits here, so this list compares firms on permits filed, license and recent activity only. Side by side: permits filed, license status and permits in the last 12 months for each firm. Pick what you value and the list re-orders.
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Top 5 by ADU permits filed in the last 12 months. This is volume, not quality: a busy firm is not necessarily a careful one.
The 8 ZIP codes with the most ADU permits on homes from October 2023 to September 2026. Each opens permits by trade and the most active firms there.
94941 (35) 94904 (30) 94903 (13) 94960 (8) 94924 (5) 94901 (4) 94970 (3) 94937 (2)
Before you move a slider, the list is in a default order built only from the permit record: how much of each firm’s record is this kind of job (weight 30) and how many permits it filed in the last 12 months (15). Each measure is ranked against the other 99 firms and pulled toward the middle when a record is short; a firm with a matched license problem is listed last.
The order comes from the Marin County permit file, not from reviews: 37 of 99 ADU builders filed a permit in the last 12 months. Nobody pays to be listed or to move up, and there are no star ratings or reviews. The sliders and presets change the weights, and the order changes with them. How the records work in Marin County.
We do not rate contractors. In this page’s default order, which uses only the permit record through Sep 2026, the top 3 are Emr Construction Inc (4 permits), Cohan Structures (3 permits) and Kelly Domer Partners Inc. dba Pacific Constr (3 permits).
99 firms are on the list; the busiest filed 2 ADU permits in the last 12 months and the middle firm filed 1 in the whole file. Line them up on the same public measures: permits filed, usual filed job value and license status. Pick what matters to you and the list re-orders, for example recent activity if you need someone soon. The order comes from the permit record only, and nobody pays to be listed or to move up.
99 firms filed at least one ADU permit on homes in unincorporated Marin County from October 2023 to September 2026; 37 of them filed one in the last 12 months.
93 of the 99 ADU builders on the Marin County permit file match an active license, 3 match one that is expired, suspended or inactive, and 3 we could not match. A firm we could not match is not proven unlicensed: the match is by company name. Look any firm up by name or license number with CSLB license check; statuses show under each firm’s name above. How to check a contractor's license in California →
Three you can check against this page: “How many ADU permits have you filed in Marin County?” (the middle firm here filed 1; 37 of 99 filed one in the last 12 months); “What value will you put on the permit?” (the usual filed value here is $205,000); “Will you pull the permit in your company’s name, and when is the final inspection?”. All 10 questions and how to check each →
On this page: 99 firms filed 111 ADU permits from October 2023 to September 2026, and each firm’s name opens its own permit record. Every number comes from Marin County Community Development Agency building permits on homes in unincorporated Marin (the County's open-data permit and inspection files). To see one permit itself, search the address or permit number with the Marin County permit office. How the records work in Marin County →
We do not rate or collect reviews. Instead each of the 99 ADU builders here is shown with its permit record: 111 permits, usual filed value and license status. Read reviews on other sites and use this page to check them against the record. Reviews vs permit records →
Every number on this page comes from Marin County Community Development Agency building permits on homes in unincorporated Marin (the County's open-data permit and inspection files): 99 firms filed 111 ADU permits on homes in unincorporated Marin County from October 2023 to September 2026, and 37 of them filed one in the last 12 months. The middle firm has 1 permit in the whole file. A short record leaves more uncertainty, and some jobs never require a permit.
The middle recorded permit value is $205,000. That is a filed estimate, not a quote or final bill. See how we compare records.
Most Marin County ADU permits are filed in April (173 against an average month of 100); February is the quietest (32). When each trade is busiest in Marin County →