Fast, Reliable New Detached ADU Across Eastvale
A new detached ADU in Eastvale typically runs $220,000-$380,000 all-in, from permit-ready drawings through final inspection, and most projects clear permitting in 4-6 months on these large Chino Valley lots. We’re Nadia Ellery’s team at Ellery ADU Studio Anaheim, and our Inland Empire office coordinates design, permit sets, and construction for Eastvale homeowners specifically. We know the tract stock here - the 2000-2015 wood-frame builds off Hamner Ave, the deep rear yards in Eastvale Ranch, the 3-car garages that change your options. Call (657) 366-5740 to schedule your free estimate; every project ships with a written price before any work starts, per Haven Standard Clause 1.
Why Ellery ADU Studio Anaheim Is Eastvale’s Preferred New Detached ADU Company
We’ve designed, permitted, and built ADUs across the Inland Empire since 2015 - the year California’s ADU laws shifted - and Eastvale’s lot geometry keeps us busy. The 7,500-10,000+ sq ft parcels carved from former dairy farmland mean we rarely file for setback variances here. That saves months.
Our crews are background-checked, uniformed, and licensed; the license number appears on every page and every contract. We don’t subcontract the design out and hope the builder can read the drawings. Our New Detached ADU team handles both under one contract at one written price, so when the inspector flags something, there’s no designer-versus-builder blame gap to stall your project.
Response time to Eastvale is same-week for initial site visits, scheduled from our Inland Empire office. A live person answers calls 24/7 - no voicemail queue, no callback promise that doesn’t materialize. And we offer a Free Second Opinion on any written estimate you already have in hand.
Our 365-Day Done Right Promise is backed in writing before your project starts: if the finished ADU isn’t built to the permitted drawings, we make it right. Not a handshake. A clause.
Our New Detached ADU Services in Eastvale
Custom Built ADU
Custom built ADUs in Eastvale typically run $260,000-$380,000 all-in. We design for your specific lot - the west-facing rear yard that bakes in afternoon sun, the slope that drains toward the alley, the existing mature trees you want to keep. Every custom project ships with a full permit set, engineered for Eastvale’s specific soils and Title 24 requirements. We write framing and utility allowances into the contract before demo, based on what we find during our initial inspection of your 2000-2015 tract home.
Prefab ADU Installation
Prefab ADU installation in Eastvale typically runs $220,000-$320,000 all-in, including site prep, foundation, utility tie-ins, and finish work. We specify and coordinate Abodu and Cover systems within our single-contract model - no separate purchase from the factory and separate contractor for the pad. Because Eastvale’s deep lots accommodate standard module dimensions without crane gymnastics, prefab delivery and set-day logistics are straightforward. We handle the Eastvale permit set, the factory coordination, and the site work as one scope, one written price.
Modular ADU
Modular ADU projects in Eastvale typically run $240,000-$350,000 all-in. We work with Dvele and other modular systems, specifying factory-built volumes that ship complete and get craned onto your prepared foundation. Eastvale’s wide streets and lack of overhead utility conflicts in newer tract areas make crane positioning easier than in older Inland Empire neighborhoods. The permit set addresses local foundation requirements, utility trenching, and the specific tie-in points to your main house’s panel and sewer lateral.
Studio ADU
Studio ADUs in Eastvale typically run $220,000-$280,000 all-in. These 400-500 sq ft units fit comfortably within standard setback and lot coverage limits on Eastvale’s large parcels. We size the mini-split for the actual exposure - a west-facing studio in Eastvale Ranch needs more cooling capacity than the east-facing equivalent - and we spec insulation above Title 24 minimums because summer highs of 105-110°F in the Chino Valley heat basin will test any building envelope.
1-Bed & 2-Bed ADU
1-bed ADUs in Eastvale typically run $240,000-$320,000; 2-bed units run $280,000-$380,000. These full-size detached units are where Eastvale’s lot geometry shines. A 750 sq ft 2-bed with kitchen and bath clears setbacks on a standard 7,500 sq ft lot without variance - impossible in Corona or Chino Hills where the same plan would require a discretionary review. We design for the actual bedroom count, the actual window placement for natural light and egress, and the actual electrical load of modern appliances on a panel that was never sized for this.
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Eastvale
We specify and coordinate prefab and modular systems from Abodu, Cover, and Dvele within our single-contract model - not as separate purchases you coordinate yourself. For site-built work, we use James Hardie siding systems where the design calls for durable exterior finishes that handle Eastvale’s thermal cycling and intense UV exposure. Every brand selection is documented in the permit set and locked at contract signing under Haven Standard Clause 5 (No Surprises). No door-side swaps, no “while we’re here” upgrades.
Common New Detached ADU Problems We See in Eastvale Homes
- Undersized or damaged framing at the house-ADU connection. On Eastvale’s 2000-2015 builds, we regularly find that a prior owner removed a patio cover or added an unpermitted rear structure and left the framing compromised. We inspect for this before demo and write a framing allowance into the contract, so the repair is priced and approved in writing before we touch it.
- Outdated wiring and panel capacity. These tract homes were wired for the original owner’s load - no ADU subpanel, no heat pump, no electric vehicle charger in the garage. The moment we calculate your detached unit’s electrical demand, the panel limit shows up. We price the service upgrade or subpanel routing as a line item in the initial contract, not as a mid-project surprise.
- Failed waterproofing at old patio slabs or rear wall flashing. Eastvale’s hardpan soils and occasional winter rains mean water finds any gap at the house foundation. When we excavate for the new ADU footing, we often find deteriorated flashing or a cracked patio slab that was hiding under pavers. We document it with photos, price the repair, and get written approval before proceeding - part of our documented photo record on every visit.
- Undersized HVAC for 105-110°F Chino Valley summers. Title 24 minimums are a floor, not a recommendation. A mini-split sized for mild coastal weather will fail here. We spec for actual east-west exposure, roof color, and natural shading - and we oversize insulation because the difference between comfortable and uninhabitable in August is R-value you can’t see.
Pricing for New Detached ADU in Eastvale, CA
| ADU Type | Typical Range (All-In) | What Drives the Number |
|---|---|---|
| Studio ADU (site-built) | $220,000-$280,000 | Foundation type, utility trench length, finish level |
| 1-Bed ADU (site-built) | $240,000-$320,000 | Kitchen spec, bathroom layout, electrical service upgrade |
| 2-Bed ADU (site-built) | $280,000-$380,000 | Square footage, second egress window, full appliance package |
| Prefab/Modular (installed) | $220,000-$350,000 | Module count, factory lead time, crane access |
These ranges reflect Eastvale’s specific conditions: large lots that avoid variance costs, 2000-2015 construction that minimizes asbestos and plumbing surprises, and summer heat that demands HVAC and insulation upgrades above code minimum. What moves a quote within these bands is the condition of your existing utilities, the distance from house to proposed ADU pad, and whether we find unpermitted prior work that needs correction.
Every project is quoted with a written price before any work begins - Haven Standard Clause 1. No “call for a quote” here. Call (657) 366-5740 for your free estimate.
We Also Serve Cities Near Eastvale
Our New Detached ADU in Eastvale crews also work in Anaheim, Yorba Linda, Villa Park, and Orange. Each city has different lot coverage rules, setback tables, and utility coordination requirements; we permit and build specifically for each jurisdiction’s actual code, not a regional template.
Serving Eastvale, CA - Our Local Coverage Area
We’re based in the Eastvale 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 Eastvale
Because the 2000-2015 tract homes here were built with no ADU in mind, and prior owners often left surprises - unpermitted patio covers removed without proper framing repair, wiring that doesn’t meet current load calculations, or failed waterproofing hidden under hardscape. We handle this by inspecting before demo, writing specific allowances into your contract, and pricing any discovered issue with photos and written approval before we proceed. Call (657) 366-5740 for an exact quote - estimates are free.
Yes. Eastvale’s 7,500-10,000+ sq ft lots, carved from former Chino Valley dairy farmland, routinely accommodate full-size detached ADUs within standard setbacks and lot coverage limits. The same plan in Corona or Chino Hills often requires a variance or reduced footprint. This is why we site detached units behind the garage on Eastvale properties rather than defaulting to garage conversions. Call (657) 366-5740 to see what your specific lot allows.
No. A detached ADU is separate from the garage by definition. On Eastvale’s common 3-car garage homes, we typically keep all garage bays intact and site the new unit in the deep rear yard. If you’re interested in converting the third bay instead, that’s a different project - a garage conversion ADU, not a detached ADU. We can quote either, but this page is for new detached units that stand alone. Call (657) 366-5740 to discuss which path fits your goals.
We spec a mini-split heat pump sized for the actual exposure and shading of your specific lot, with cooling capacity above the Manual J calculation for east-west orientation and roof color. Insulation exceeds Title 24 minimums - we’ve found that code-minimum R-values in a west-facing detached unit lead to comfort complaints and high electric bills in August. The exact spec is documented in your permit set and locked at contract. Call (657) 366-5740 for details on your property.
Expect electrical service or subpanel upgrades to handle the ADU load, fire-rated separation at any connecting roofline or breezeway, and enhanced insulation and glazing for Title 24 compliance. If we find failed waterproofing or compromised framing during excavation or tie-in, the inspector will flag it - which is why we build allowances into the contract and document everything with photos. No change order appears without your written approval. Call (657) 366-5740 to walk through the specific code path for your project.
Written by Nadia Ellery, Owner at Ellery ADU Studio Anaheim, serving Eastvale since 2015.