640 ADU builders filed 1,278 ADU permits on homes in the City of San Diego from October 2023 to September 2026; 258 filed one in the last 12 months. The middle filed job value was $127,372. The most active in the last 12 months were 1PLUS Studio (28 permits), Ballow Construction Inc (13) and Infill Innovation Inc (13); busy is not the same as careful. Side by side: permits filed, share finished, 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.
92115 (131) 92117 (129) 92104 (79) 92114 (78) 92111 (76) 92107 (69) 92109 (67) 92105 (65)
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), how often its permits reached completion (25), how many permits it filed in the last 12 months (15) and how quickly its permits closed (10). Each measure is ranked against the other 640 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 San Diego permit file, not from reviews: 258 of 640 ADU builders filed a permit in the last 12 months and 73% of their permits a year or more old were finished. 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 San Diego.
We do not rate contractors. In this page’s default order, which uses only the permit record through Sep 2026, the top 3 are Snapadu (27 permits, 94% finished), Ballow Construction Inc (13 permits) and Infill Innovation Inc (13 permits). By permits filed alone, the most active is 1PLUS Studio with 36.
640 firms are on the list; the busiest filed 28 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, share of permits finished, 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.
640 firms filed at least one ADU permit on homes in the City of San Diego from October 2023 to September 2026; 258 of them filed one in the last 12 months.
333 of the 640 ADU builders on the San Diego permit file match an active license, 22 match one that is expired, suspended or inactive, and 285 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 San Diego?” (the middle firm here filed 1; 258 of 640 filed one in the last 12 months); “What value will you put on the permit?” (the usual filed value here is $127,372); “Will you pull the permit in your company’s name, and when is the final inspection?” (73% of older ADU permits here were finished). All 10 questions and how to check each →
On this page: 640 firms filed 1,278 ADU permits from October 2023 to September 2026, and each firm’s name opens its own permit record. Every number comes from City of San Diego Development Services approvals. To see one permit itself, search the address or permit number with the San Diego permit office. How the records work in San Diego →
We do not rate or collect reviews. Instead each of the 640 ADU builders here is shown with its permit record: 1,278 permits, the share finished, 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 City of San Diego Development Services approvals: 640 firms filed 1,278 ADU permits on homes in the City of San Diego from October 2023 to September 2026, and 258 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 $127,372. That is a filed estimate, not a quote or final bill. See how we compare records.
Most San Diego ADU permits are filed in April (134 against an average month of 100); September is the quietest (58). When each trade is busiest in San Diego →