ADU Builder in Roseville, CA
Thinking about adding an ADU to your Roseville property? Golden Valley Development is a family-owned, licensed design-build contractor based just up the road in Loomis. We design, permit, and build custom accessory dwelling units across Roseville — from garage conversions in older Cherry Glen and Folsom Road neighborhoods to detached backyard units on the larger lots of West Roseville.
What we build in Roseville
Detached ADUs up to 1,200 sq ft — a standalone second home on your lot: guest suite, rental unit, home office, or a purpose-built leisure space with the ceiling height and power for a golf simulator, gym, or theater.
Attached ADUs — a seamless addition that shares a wall with your main home, often the most budget-efficient path to a full second dwelling.
Garage conversions — turn an underused garage into a legal, permitted living space; one of the fastest routes to rental income in Roseville’s established neighborhoods.
Junior ADUs (JADUs) — compact units up to 500 sq ft within your existing footprint.
Roseville ADU rules, handled for you
Most residential parcels in Roseville can hold a primary home, an ADU, and a junior ADU — three dwellings on one lot under current California law. Every project needs permits, plan review, and inspections through the City of Roseville, and utility connections are handled through Roseville Electric. We manage site planning, engineering, and permitting in-house, so you deal with one team from the first 3D concept to final walkthrough.
What a Roseville ADU costs
Most of our custom ADUs land between $150,000 and $400,000 depending on type, size, and site conditions. Garage conversions start lower; large detached units with custom finishes run higher. See our full ADU cost guide for 2026 ranges by type, or skip straight to a real number for your lot with a free site assessment.
Why Roseville homeowners choose Golden Valley
We’re local — Loomis-based, CSLB licensed (#1030793) and insured, and we build to current ADU codes with one crew from design through keys. You’ll see your ADU in 3D before we break ground, and we’re currently taking $1,000 off design.
Get your free Roseville site assessment → or call (916) 671-0802. We’ll confirm what your parcel allows and sketch a first concept — free, no obligation.
Also serving Rocklin, Loomis, Granite Bay, Folsom, and greater Placer County.