Block12 Construction
License #1033146 · activelicensed since 2017Bbased in San Franciscobond $25kworkers’ comp: carriernot on Yelp
Named as contractor on 5 ADU projects in San Francisco (and 77 permits of any kind). Verify at CSLB before hiring.
ADU projects
5
2 garage conversion · 1 ground-floor conversion · 1 ADU
Declared cost (middle half)
$150k–$432k
median $218k
Build time
1 year 8 months
median, issued → completed
Open · finished
3 · 2
Their ADU projects
- 1 Mallorca WayMarinaConverted · ground-floor conversionCompleted11 permitsdeclared $922k for 3 ADUsfiled Mar 2023permit 1 year 4 monthsbuilt 6 months · done Jan 2025ADU permit 202303173911 · city record · flagged ADU by SF DBI
- 1460 Golden Gate AveWestern AdditionConvertedPermit issued, in progress2 permitsdeclared $432k for 2 ADUsfiled May 2021permit 4 years 2 months1 year 3 months since issueADU permit 202105261110 · city record · flagged ADU by SF DBI
- 2160 Fell StLone Mountain/USFConverted · garage conversionPermit issued, in progress1 permitdeclared $150k for 3 ADUsfiled Nov 2020permit 3 years 7 months2 years 4 months since issueADU permit 202011289777 · city record · flagged ADU by SF DBI
- 2150 Fell StLone Mountain/USFConverted · garage conversionPermit issued, in progress3 permitsdeclared $50kfiled Nov 2020permit 3 years 7 months2 years 4 months since issueADU permit 202011289774 · city record · flagged ADU by SF DBI
- 575 Pierce StHayes ValleyConvertedCompleted9 permitsdeclared $218kfiled Aug 2019permit 2 years 10 monthsbuilt 2 years 9 months · done Feb 2025ADU permit 201908158936 · city record · flagged ADU by SF DBI
Each row is one project: the ADU permit plus its revisions, sub-permits and trade permits. Dates are the city’s.