How much does an ADU cost?

Most detached ADUs land between $135,000 and $255,000 all-in, depending on size and site conditions.

How long does it take?

Design and permitting typically run 3–5 months; construction runs 4–7 months after permits are issued.

Do you handle permits?

Yes — plan check submittal, corrections and inspections are managed in house at no extra hourly cost.

California state law allows ADUs to be rented at 30-day-plus terms in every jurisdiction we build in.

Custom Home Builder Folsom, CA

Custom Home Builder Folsom, CA — quick facts

Custom home builder serving Folsom — Empire Ranch, Folsom Ranch, Briggs Ranch, Russell Ranch. Fixed-price design-build. CSLB #1094366. (866) 797-7653. A1 Building Contractors LLC is a veteran-owned, licensed general contractor serving the greater Sacramento region. Every project starts with a review of the property, the local jurisdiction and the homeowner's goals.

Licensed California general contractor — CSLB #1094366, DRE #00898265.
Veteran-owned and based in Roseville, serving Sacramento, Placer and El Dorado counties.
Scope covers detached ADUs, attached ADUs, JADUs, garage conversions, home additions and custom homes.
Plans, permits, plan check and construction are coordinated in-house for Custom Home Builder Folsom, CA.
Typical detached ADU budgets run about $135K to $255K depending on size and site conditions.

Local guidance for Custom Home Builder Folsom, CA

A1 Building Contractors LLC helps Sacramento-area and Placer County homeowners evaluate design, permitting, site access, utilities, construction scope and realistic project costs before work begins. Each project is reviewed against the property, local jurisdiction and homeowner goals rather than a one-size-fits-all estimate.

For Custom Home Builder Folsom, CA, our team can explain practical options, likely approval steps and the tradeoffs that affect schedule and budget. Homeowners receive a clear path from initial feasibility through plans, permits and construction, with recommendations grounded in local building requirements and build conditions.

A productive first review considers available lot space, setbacks, access for construction, utility locations, desired square footage and long-term use. Those details help identify constraints early, compare appropriate project approaches and avoid spending on a design that does not fit the site or local rules. A1 then coordinates the applicable design and construction stages with clear decisions at each milestone.

Custom Home Builder in Folsom, CA

Folsom has become one of the most active custom-home markets in Sacramento County — driven by Folsom Ranch, Empire Ranch, Briggs Ranch, Russell Ranch, and the new build-out south of Highway 50. The City of Folsom Community Development department is one of the more efficient plan-check operations in the region, which makes Folsom a good market for a tight design-to-permit timeline. A1 Building Contractors is veteran-owned, CSLB-licensed (#1094366), and a California licensed Broker (#00898265). We build new custom homes on Folsom infill lots and in the master-planned communities, handle ARC design review, and run the whole project on one contract with a fixed price. No teaser pricing, no $40K change-order surprises. Tell us your lot and finish level, get a real number.

City: Folsom, Sacramento County
Design, engineering, permitting and construction under one contract
Veteran-owned · CSLB #1094366

How we deliver Custom Home Builder Folsom, CA

Every project runs through the same five-stage process, so you know what happens next and what it costs before construction starts. We handle design, engineering, jurisdictional plan check and construction under one contract, which keeps the schedule and the budget with a single accountable team.

Stage 1 — Site walk and feasibility: setbacks, utilities, easements and lot coverage reviewed on site
Stage 2 — Fixed-scope proposal: line-item pricing with permits, utility connections and finishes included
Stage 3 — Design and engineering: architectural plans, Title 24 energy calcs and structural engineering
Stage 4 — Permitting and plan check: submittal, corrections and approvals handled by our office
Stage 5 — Construction and closeout: weekly updates, final inspection, certificate of occupancy and warranty

Common questions about Custom Home Builder Folsom, CA

The three questions homeowners ask most, answered plainly. Pricing reflects 2026 Sacramento-region construction costs including permits, utility connections and standard finishes.

How much does an ADU cost? Most detached ADUs land between $135,000 and $255,000 all-in, depending on size and site conditions.
How long does it take? Design and permitting typically run 3–5 months; construction runs 4–7 months after permits are issued.
Do you handle permits? Yes — plan check submittal, corrections and inspections are managed in house at no extra hourly cost.
Can I rent it out? California state law allows ADUs to be rented at 30-day-plus terms in every jurisdiction we build in.

Why homeowners choose A1 for Custom Home Builder Folsom, CA

A1 Building Contractors LLC is a veteran-owned, CSLB-licensed general contractor serving the greater Sacramento region. We design, permit and build ADUs, garage conversions, home additions and custom homes across the Sacramento region, with transparent line-item pricing and a single point of contact from first site walk to final inspection.

CSLB #1094366 General Contractor · DRE #00898265 Broker
Serving Sacramento, Placer, El Dorado, Yolo and Sutter counties
In-house design, permitting, plan check and construction
Call (866) 797-7653 for a same-day callback