Building an Accessory Dwelling Unit in San Francisco: Everything You Need to Know in 2025

Thinking about building an accessory dwelling unit in San Francisco? Discover 2025 rules, permit steps, costs, and how R.C.R Contractors guides you from planning to move-in. Accessory dwelling units, also known as ADUs or backyard homes, are one of the smartest investments San Francisco homeowners can make in 2025. Whether you want extra rental income, space for family, or to increase your property’s value, building an ADU can make it happen. But in San Francisco, it is not just about putting up walls. There are rules, permits, and planning hurdles. Luckily, R.C.R Contractors has the local experience to make the entire process smooth from day one. What Is an ADU, and Why Build One? An Accessory Dwelling Unit is a secondary residential space on the same lot as a primary home. It can be attached or detached and usually includes its own kitchen, bathroom, and entrance.In San Francisco, ADUs have become increasingly popular because of their flexibilit...