ADU Design & Permitting Near Me in Chino - Design, Permits and Build Under One Contract

ADU Design & Permitting Near You in Chino, CA

If you’re searching for our ADU Design & Permitting services near Chino, Ellery ADU Studio is based here and works across the Inland Empire – drawings, permit set, and construction under one written contract at one written price. Nadia Ellery leads every project, and a live person picks up the phone at (909) 323-1107 around the clock, no voicemail queue. We serve Chino, Chino Hills, Eastvale, Ontario, Montclair, Pomona, Diamond Bar, and Corona.

Since 2015, we’ve designed, permitted, and built more than 900 ADUs across this region. Every single one started with a written price before any work began – that’s Haven Standard Clause 1, and it’s not optional on our end. The homeowners we work with have usually already read the horror stories: a designer hands off permit drawings that the builder says are wrong, and suddenly no one is responsible. Our one-contract model eliminates that gap by design.

If you already have a written estimate from another firm, we’ll give you a free second opinion on it – specific line by line, not a vague “we can do better.” Call (909) 323-1107 to schedule that conversation.

• Written price before any work starts – Haven Standard Clause 1, on every project, no exceptions
• One contract covers design, permit drawings, and construction – no designer-versus-builder blame gap
• 365-Day Done Right Promise – if the finished ADU doesn’t match the permitted drawings, we make it right, in writing, before your project starts
• Live person 24/7 – not a callback promise, an actual answer
• Free second opinion on any written estimate already in hand
• 900+ ADUs designed, permitted, and built since 2015 – each with a documented photo record

Fast, Local ADU Design & Permitting

Being based in Chino means we already know the City of Chino’s Planning Division requirements, the San Bernardino County overlay rules that sometimes apply to properties at the city’s edge, and the specific quirks of Chino’s older residential zones – areas like Preserve neighborhoods and the subdivisions along Eucalyptus Avenue where lot configurations create setback questions that trip up out-of-area designers.

When you call (909) 323-1107, a live team member answers and can schedule a same-day or next-business-day site assessment depending on your calendar. We don’t hold permit slots artificially scarce – we schedule when it works for you. The Site Assessment produces a written scope and a written price, both delivered before any design work begins. That’s the sequence: assess, document, price in writing, then start drawings.

For homeowners in Chino weighing a garage conversion, a new detached ADU, or a junior ADU carved from existing interior space, the permitting timeline in Chino typically runs 8 to 14 weeks from complete application submission to permit issuance, depending on project type and current city backlog. We factor that timeline into the written project schedule you receive at signing – no surprises on pacing.

Areas We Cover

Ellery ADU Studio is rooted in Chino but regularly works across the western Inland Empire and the eastern edges of Los Angeles County. The cities below represent our active service area – if your address falls outside this list, call us and we’ll tell you directly whether we can serve you.

Chino is our home base, and our ADU Design & Permitting in Chino page covers the city’s specific zoning rules, lot size thresholds, and cost ranges in detail. The city operates under California’s state ADU law with local amendments, and our permit sets are built to that exact standard.

Chino Hills sits just south along the 71 corridor. Properties here often carry more complex topography – hillside lots, steeper grades, and the occasional geologic review requirement – all of which we account for in site assessment and drawings before the Permit Application goes in.

Eastvale is a relatively young city incorporated in 2010, and its Planning Department processes ADU applications through Riverside County’s legacy review framework in some cases. We’re current on that process and have active projects in the area.

Ontario has a strong track record of ADU approvals, particularly for detached units on standard R-1 lots. The city’s permit counter is efficient relative to many Inland Empire municipalities, which benefits our clients’ schedules.

Montclair is a smaller city with straightforward ADU zoning, though its lot coverage rules require close attention on the more compact residential parcels common in the city’s older neighborhoods near the Montclair Place area.

Pomona presents a mix of older housing stock – many homes built pre-1980 with detached garages that are strong candidates for conversion ADUs, though electrical panel upgrades and foundation assessments are a consistent line item in our written scopes here.

Diamond Bar homeowners typically sit on larger lots in the hills, which opens up new detached ADU possibilities. HOA & Zoning Compliance overlap in several Diamond Bar neighborhoods, and we review both before drawing anything.

Corona falls in Riverside County and operates under its own permitting structure. We’ve worked through Corona’s Building & Safety Department on multiple projects and are familiar with its plan check process.

For a broader look at who we are and what the design-build model covers, visit our home page.

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What ADU Design & Permitting Costs Near Chino

This is the section most ADU websites skip. We don’t, because a written price is the entire point of how we work.

Design and permitting fees – meaning the architectural drawings, structural calculations, Title 24 energy compliance report, and permit application preparation – are a distinct cost from construction. Here’s how those ranges typically land in Chino and the surrounding service area:

Every number above is a range – your written price from Ellery will be a fixed figure, not a range, and it will be on paper before any work begins. Under Haven Standard Clause 5 (No Surprises), the scope is locked at signing. No door-side upsells, no scope creep mid-project.

One thing worth understanding about Chino specifically: the city’s impact fees for ADUs were recalibrated in recent years following state mandates that limited fees for units under 750 square feet. If your project falls under that threshold, permit-related city fees may be lower than an older estimate suggests. We’ll tell you exactly what the current fee schedule produces for your specific project in the written quote.

Our Services – One Contract, All Five

Ellery ADU Studio covers five service lines under a single contract. This matters because most homeowners eventually need more than one of them, and splitting the work across separate firms creates coordination gaps that cost money and add months.

• ADU Design & Permitting – full permit set: architectural drawings, structural engineering, Title 24 energy report, city application
• Garage Conversion ADU – existing attached or detached garage converted to livable space; slab assessment included in site evaluation
• New Detached ADU – ground-up construction in the rear yard; prefab coordination available for Abodu, Cover, Dvele, Mighty Buildings, Boxabl, Plant Prefab, and Tuff Shed systems
• Junior ADU & Interior Conversion – converting existing interior space, typically within the primary residence
• Site Prep & Utilities – grading, utility connections, meter installation coordination with SoCal Edison, SoCal Gas, and the Chino Valley Independent Fire District where applicable

If you’re weighing a prefab system, note that James Hardie cladding systems are specified on many of our stick-built projects as well – the fiber cement performs well in Chino’s inland climate, where summer temperature swings are more pronounced than coastal markets and wood-based siding degrades faster.

Why the Design-Build Model Changes the Math

Most ADU projects in the Chino area are structured as two separate contracts: one with an architect or designer for drawings, one with a general contractor to build. When something is wrong – a wall that doesn’t match the plans, a ceiling height that fails inspection – each party points at the other. The homeowner is stuck in the middle, sometimes for months, sometimes spending money on changes that neither party agreed to pay for.

Ellery’s one-contract model closes that gap structurally. Nadia Ellery’s team produces the drawings and builds to them. If the finished ADU doesn’t match the permitted drawings, the 365-Day Done Right Promise requires us to make it right at no additional cost – and that obligation is documented in writing before the project starts, not promised verbally after something goes wrong.

That structure is why our documented photo record matters. Every project phase is photographed and shared with the client. You don’t get a verbal update on how framing went; you get images of what was framed, tied to the approved permit drawings. That documentation is yours to keep.

Frequently Asked Questions

How fast can you start on an ADU design and permitting project near Chino?

We can schedule a site assessment as soon as the next business day in most cases – and in some situations, same-day depending on our current schedule and yours. The assessment produces a written scope and written price, both delivered before any design work begins. Call (909) 323-1107 to confirm current availability; a live person will answer and give you a straight answer on timing.

Do you serve my area if I’m not in Chino proper?

Yes – Ellery ADU Studio actively serves Chino Hills, Eastvale, Ontario, Montclair, Pomona, Diamond Bar, and Corona in addition to Chino itself. If your address sits at the edge of these boundaries, call us directly at (909) 323-1107 and we’ll confirm whether we can take the project before you invest any time in the conversation.

How much does ADU design and permitting cost near Chino?

Design and permit set preparation for an ADU in the Chino area typically runs $8,000 to $18,000 depending on unit size, structural complexity, and whether the project requires a variance or discretionary review. All-in construction costs range from roughly $95,000 for a simpler garage conversion to $380,000 or more for a larger new detached unit. Your written quote from Ellery will be a fixed number, not a range, delivered before any work starts per Haven Standard Clause 1. Call (909) 323-1107 to schedule the site assessment that produces that number.

Can I reach someone after hours if I have questions?

A live person answers calls to (909) 323-1107 around the clock – no voicemail, no callback queue. ADU projects involve real money and real timelines, and questions don’t always surface during business hours. If you’re comparing estimates at 9 p.m. or just received a city notice and want to understand what it means, call us.

Key Takeaways

• Ellery ADU Studio is based in Chino and serves Chino Hills, Eastvale, Ontario, Montclair, Pomona, Diamond Bar, and Corona under one written contract
• Design and permit sets for Chino-area ADUs typically run $8,000 to $18,000; all-in construction ranges from $95,000 to $380,000 depending on project type
• Every project starts with a written price – Haven Standard Clause 1 – before any drawings begin
• The 365-Day Done Right Promise is documented in writing before the project starts, not offered verbally after a problem surfaces
• 900+ ADUs designed, permitted, and built since 2015, each with a documented photo record
• Free second opinion available on any written estimate already in your hand
• Live person answers at (909) 323-1107 – no voicemail

Talk to Ellery ADU Studio About Your Project

If you’re ready to understand what an ADU would actually cost on your specific Chino-area property – not a range from a brochure, but a written number tied to your lot, your goals, and your city’s current permit requirements – call (909) 323-1107. A live person answers, every call, at any hour. We’ll schedule a site assessment, document what we find, and deliver a written scope and price before any design work begins. That’s how every Ellery project starts, and it’s been that way since 2015.

Written by Nadia Ellery, Owner at Ellery ADU Studio Chino, serving Chino and nearby areas.