ADU Builder in Loomis, CA

Loomis is our hometown. Golden Valley Development is headquartered right here, and we’ve built our reputation on Loomis properties — the rural acreage, horse properties, and generous lots that make this one of the best places in Placer County to add a second dwelling. When you build an ADU with us in Loomis, your builder is a neighbor.

What we build in Loomis

Detached ADUs up to 1,200 sq ft — a standalone home on your acreage: guest house, in-law residence, rental unit, or a purpose-built leisure space (golf simulator, gym, theater, studio) engineered for the activity from the ground up.

Attached ADUs — a matched addition sharing a wall and utilities with your main home.

Garage and barn conversions — Loomis properties are full of underused outbuildings and garages that can become legal, permitted living space.

Junior ADUs (JADUs) — compact in-home units up to 500 sq ft.

Loomis permitting, handled by locals

Most residential parcels can hold a primary home, an ADU, and a junior ADU under current California law. Projects in town run through the Town of Loomis; properties just outside town limits go through Placer County — we work in both systems weekly and handle site planning, engineering, Title 24 compliance, and permits in-house. Rural lots often involve wells, septic, and longer utility runs; our site assessment flags those cost drivers before you commit to anything.

What a Loomis ADU costs

Most of our custom ADUs land between $150,000 and $400,000 depending on type, size, and site conditions — see our 2026 ADU cost guide for ranges by type, or get a real number for your parcel with a free site assessment.

Your neighbors, your builder

Family-owned, CSLB licensed (#1030793) and insured, headquartered in Loomis. See your ADU in 3D before we build — with $1,000 off design right now.

Get your free Loomis site assessment → or call (916) 671-0802.

Also serving Rocklin, Roseville, Granite Bay, Folsom, El Dorado Hills, and greater Placer County.