ADU Builder in Rocklin, CA
Rocklin is one of the best places in Placer County to add an ADU — established neighborhoods, generous lots, and strong rental demand from Sierra College and the I-80 corridor. Golden Valley Development is a family-owned, licensed design-build contractor headquartered minutes away in Loomis, and we handle Rocklin ADU projects end to end: design, engineering, permits, and construction with one local crew.
ADU options for Rocklin properties
Detached ADUs up to 1,200 sq ft — a standalone backyard home for family, rental income, or a purpose-built leisure space (golf simulator, gym, theater) engineered for the activity from day one.
Attached ADUs — share a wall and often utilities with your main home for a more budget-efficient second dwelling.
Garage conversions — Rocklin’s established neighborhoods around Stanford Ranch and older Rocklin are full of underused garages that convert cleanly into legal, permitted units.
Junior ADUs (JADUs) — compact in-home units up to 500 sq ft.
Rocklin permitting, handled in-house
Under current California ADU law, most residential parcels can hold a primary home, an ADU, and a junior ADU — three dwellings on one lot. Your project runs through the City of Rocklin for plan review and inspections, and we manage all of it — site planning, structural engineering, Title 24 energy compliance, and permits — so you work with one team from 3D concept to keys.
What a Rocklin ADU costs
Most of our custom ADUs come in between $150,000 and $400,000 depending on type, size, and site conditions — garage conversions at the lower end, large detached units with custom finishes at the top. Our 2026 ADU cost guide breaks down ranges by type, and a free site assessment gets you a real number for your specific lot.
A local team you can visit
We’re based in Loomis — ten minutes from most of Rocklin — CSLB licensed (#1030793) and insured. You’ll see your ADU in 3D before we build, and we’re currently taking $1,000 off design.
Get your free Rocklin site assessment → or call (916) 671-0802.
Also serving Roseville, Loomis, Granite Bay, Folsom, and greater Placer County.