The San Marcos ADU Guide

Our ADU experience in San Marcos

SnapADU is proud to have been selected by the City of San Marcos to design their pre-approved ADU plans through a competitive bid process with over two dozen applicants. This recognition highlights our expertise in delivering high-quality, efficient, and fully compliant ADU designs as well as our experience in the city. Read more about pre-approved ADU plans.

One unusual requirement in San Marcos is that ADUs generally cannot be in the front yard (though SB-897 passed Aug 2022 will limit city’s ability to enforce this). They also require a soils report for ADUs >500 sqft. San Marcos allows for digital submissions. Turnaround times at the city are moderate.

Additionally, we have seen San Marcos projects require interaction with the Community Facilities Districts (CFD), which are commonly referred to as Mello-Roos Districts, to finance local public facilities and services. This can add months to the processing time.

What is the CFD process in San Marcos for ADUs?

A CFD is a “community facility district” that residents of the city previously voted on to create the ability for the City to collect “developer impact fees” to cover the cost associated with providing services to the residents. These fees go towards building roads, fire stations, and other public services. Every new development project in San Marcos is subject to the CFD Charge, including ADUs. California state ADU laws do not prohibit the City from assessing CFD charges.

Owners can satisfy the CFD requirement in one of two ways:
1) Vote to annex into the district, which creates a annual assessment with your property taxes (usually $1K-$2K); or
2) Pay a one -time In-Lieu Fee (typically $100K-$200K)

Only the property owners of a property/development vote on this annexation – no neighbors or 3rd parties. The City Council certifies CFD votes 4 times per year. This means that typically 3-4 months will be added to the permitting process.

San Marcos ADU Regulations & Permitting Requirements

Want to learn more about what kind of ADU you can build in San Marcos? Check out our in-depth resource guide San Marcos Regulations & Permitting Requirements outlining the ADU building code requirements. We also include what we have learned about how the city will interpret code based on actually designing & building in the city. You can also set up a consult if you want our advice on what you can build.