Fast, Reliable New Detached ADU Across Foothill Farms
A new detached ADU in Foothill Farms typically runs $185,000 to $340,000 all-in, from the first site survey through Sacramento County’s final inspection, with most 1-bed units landing between $205,000 and $275,000. That’s the honest range we quote before any work begins, because Ellery ADU Studio puts the written price in your hands before you sign anything. We’ve designed, permitted, and built detached ADUs across this unincorporated Sacramento County community since we opened our doors in 2015, and we know exactly what the County’s Building Permits and Inspection Division will flag before they flag it. Call (971) 497-2402 for a written quote on your specific lot.
Foothill Farms is different from your neighbors in Citrus Heights or the City of Sacramento. You’re not in a city at all. Every permit goes through Sacramento County, which changes the setback math, the review timeline, and the inspections. You want a team that already knows that.
Why Ellery ADU Studio Is Foothill Farms’s Preferred New Detached ADU Company
We’ve driven Walerga Road, Elkhorn Boulevard, and Roseville Road enough times to know the ranch houses, the half-acre lots, and the detached garages that sit way too close to the back fence. Our New Detached ADU team has built detached units throughout Foothill Farms, and we understand the specific tension this community creates: 1950s-era lots that feel spacious but hide setback problems the moment you try to build anything new.
The thing that separates our studio from a standard contractor is the single-contract model. The drawings, the permit set, the excavation, the foundation, the framing, the mini-split install, the final paint: one contract, one written price, one accountable team. There is no designer who blames the builder and no builder who blames the designer. Nadia Ellery founded this studio on that principle, and she still reviews every permit set that leaves our Sacramento office for a Foothill Farms site plan.
Our Foothill Farms customers get the same thing every other client gets: a written price before any work starts, a documented photo record of every site visit, and a 365-Day Done Right Promise in writing. If the finished ADU isn’t built to the permitted drawings, we make it right. That’s not a marketing line. It’s Haven Standard, Clause 5.
Our New Detached ADU Services in Foothill Farms
Most Foothill Farms homeowners come to us with one of four goals. A rental unit for long-term income. A place for aging parents that’s close but separate. A home office or studio away from the main house. Or a workshop that doesn’t eat the garage. Here’s how we scope each one.
Custom Built ADU
A custom detached ADU on a Foothill Farms lot means we design to your exact setback reality, your acreage, and your drainage pattern. On the wide lots off Walerga Road, that often means a 1-bed with a full bath, a small kitchen, and a mini-split on a concrete pad. We draw the permit set, submit to Sacramento County BSAS, and build it. You get the documentation: the site plan, the structural drawings, the Title 24 energy report, the photo record. Typical range: $220,000 to $340,000 depending on size and trenching distance from the main panel.
Prefab ADU Installation
We specify and coordinate prefab systems from Abodu, Cover, and Dvele for Foothill Farms homeowners who want the predictability of a factory-built shell with the site work handled locally. A prefab still needs a foundation, utility trenching, a mini-split, and a Sacramento County permit. The factory doesn’t handle any of that. We do, under one contract. Typical range: $185,000 to $290,000 including site prep, foundation, utility connections, and the county’s required inspections.
Modular ADU
Modular construction shares the factory-built advantage but typically arrives in more pieces, which gives you more layout flexibility on an irregular Foothill Farms lot. We’ve coordinated modular units from Mighty Buildings and others where the homeowner needed a 2-bed floor plan that a single-box prefab couldn’t deliver. Site work and grading still run through us. Typical range: $210,000 to $310,000.
Studio ADU
A studio detached ADU is the most common request we see from Foothill Farms homeowners with an existing detached garage they want to replace. Ranges from 400 to 600 square feet, one open living space, a bath, a kitchenette, and a mini-split. On a 6,500-square-foot lot, this is often the only footprint that fits without triggering the setback headaches we’re about to describe. Typical range: $185,000 to $240,000.
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Foothill Farms
We don’t manufacture prefab units. We specify them, coordinate the factory order, and handle every piece of site work that makes the unit legal and livable in unincorporated Sacramento County. That includes Abodu, Cover, and Dvele, the three brands we most frequently place on Foothill Farms lots. When a prefab unit arrives on a flatbed at a Foothill Farms address, our crew is there to set it, connect the utilities, pass the county inspections, and document the whole thing. We also stock the common parts that keep a new detached ADU running through a Sacramento Valley summer: mini-split line sets, insulated supply line materials, and the connectors that fail first when temperatures swing from 105°F in August to a frozen Tule fog night in January.
Common New Detached ADU Problems We See in Foothill Farms Homes
- The rear-lot-line garage trap. Many Foothill Farms detached garages were built in the 1950s right at the back property line, under setback rules that no longer exist. Today Sacramento County allows a 4-foot rear and side setback for ADUs, but if that old garage is a legal nonconforming structure, the county may demand corrective action before you can touch it. We verify the current status with BSAS before we quote, so you’re not blindsided in plan check.
- The 60-amp sub-panel surprise. Original ranch houses in this community often still carry a 60-amp sub-panel in the detached garage. A new detached ADU with a mini-split, a kitchen, and a bathroom needs a real electrical feed. On a half-acre lot where the new ADU sits 150 feet from the main panel, the trench alone can add $8,000 to $15,000 to the project. We scope this line item before quoting, never after.
- Drainage and the Tule fog swale. Open lots collect water, and Foothill Farms winters bring ground-level fog and periodic freeze nights. A foundation placed in a low corner without proper grading becomes a damp, frozen problem by February. We grade the pad, set the mini-split condenser on a raised base, and insulate every exposed supply line as a baseline, not an upgrade.
- The slab foundation plumbing problem. Most 1950s detached garages here sit on a 4-inch slab. Adding a bathroom means cutting that slab for plumbing rough-ins, and if the slab has settled or cracked over seven decades, the plumbing line item grows. We inspect and document the slab condition in the photo record before we write the number, so the price you see is the price you pay.
Pricing for New Detached ADU in Foothill Farms, CA
Here’s the honest math for a new detached ADU in Foothill Farms, written the way we’d put it on a proposal:
- Studio ADU (400-600 sq ft): $185,000 to $240,000
- 1-Bed Detached ADU (600-800 sq ft): $205,000 to $275,000
- 2-Bed Detached ADU (800-1,000 sq ft): $260,000 to $340,000
- Prefab or modular unit, site work included: $185,000 to $310,000 depending on brand and trenching distance
What moves the number on your specific Foothill Farms lot? The distance from the main electrical panel to the new ADU site, the condition of the existing garage slab if you’re demolishing and reusing the pad, the amount of grading and drainage work the open lot requires, and whether the county flags the existing structure’s setback status. Under Haven Standard Clause 1, you receive a written price before any work begins. No “call for a quote.” No door-side change orders. Call (971) 497-2402 for your free estimate.
We Also Serve Cities Near Foothill Farms
Our crews cover Foothill Farms directly and reach the surrounding metro areas when the project warrants it. We’ve built detached ADUs for homeowners in Los Angeles, San Diego, San Jose, and San Francisco, often on lots where the local building department’s rules differ significantly from what Sacramento County requires here. That cross-county experience helps us spot ordinance quirks early, before they become plan-check delays.
Serving Foothill Farms, CA - Our Local Coverage Area
We’re based in the Foothill Farms area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - New Detached ADU in Foothill Farms
You need a Sacramento County permit. Foothill Farms is unincorporated, not part of Citrus Heights or the City of Sacramento, so every new detached ADU permit runs through Sacramento County’s Building Permits and Inspection Division under the County’s ADU ordinance. No city code applies to your lot. This changes the setback rules, the fee schedule, and the inspection workflow. Call (971) 497-2402 and we’ll map out exactly which county forms and submittals your project requires.
Usually yes, but the sequence matters. Sacramento County allows a 4-foot rear and side setback for new ADUs, which is good news. The risk is that your 1950s garage was built under older rules and now sits as a legal nonconforming structure at the property line. If BSAS flags that status, you could face a variance or redesign that adds weeks and thousands. We verify the garage’s nonconforming status with the county before we quote. That’s the only way to give you a real number. Call (971) 497-2402 to start that verification.
Sacramento County enforces minimum horizontal distances between new dwelling units and existing septic tanks, leach fields, and wells. A new detached ADU on a larger acreage parcel must sit far enough from the septic system and the well head to satisfy county environmental health requirements, which can push the placement and add trenching distance for water and sewer lines. We measure these distances during the site survey before we quote. Call (971) 497-2402 for a written scope on your parcel.
It’s non-negotiable. Sacramento Valley summers exceed 100°F for weeks at a time, and Sacramento County treats mechanical cooling as a habitability requirement for a detached dwelling unit, not an optional upgrade. A ductless mini-split is the standard solution, and it must be sized to the specific square footage and orientation of your ADU. We include it in every written quote for Foothill Farms. Call (971) 497-2402 and we’ll walk you through the sizing for your lot.
Expect some grading. Open lots here collect water in the winter, and the Tule fog season means the ground stays damp for weeks. We typically grade the building pad to slope away from the foundation, raise the mini-split condenser on a concrete base above the winter water line, and insulate every exposed supply line against freeze nights. On a half-acre parcel with a low corner, that work can run $3,000 to $8,000 and should be in the written quote from day one, not discovered in February. Call (971) 497-2402 for a free estimate that includes drainage work, because leaving it out is how budgets blow up.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Foothill Farms since 2015.