A curated directory of vetted builders that add an accessory dwelling unit attached to or as an extension of the existing home. builders
Frequently Asked Questions
How do I choose a builder for a attached adu project?
Shortlist only contractors who are actively CSLB-licensed (Class B), bonded, and insured, with verifiable recent attached adu projects and real permitting experience. Our directory highlights each builder's specialties, license status, and CSLB number so you can compare confidently — then request an intro to a verified builder matched to your project.
What should I expect from a attached adu builder?
A qualified attached adu builder should provide a fully itemized fixed-price quote (with utility connections named as a line item), handle permitting for you, and collect no more than a $1,000 deposit up front — California's legal cap. Be wary of any "material reservation" or "lumber-lock" fee that pushes your up-front payment higher; that's a red flag for an illegal deposit.
How long does a attached adu project take?
Timelines vary by scope and city review, so be skeptical of anyone guaranteeing a fixed "60-day approval" — that statutory deadline applies only to a complete application and isn't a real-world build timeline. In Los Angeles, custom ADU permitting realistically runs about 3–6 months, with design-to-move-in around 8–14 months. A verified attached adu builder will give you an honest, project-specific schedule.