ADU Before & After in Chino, CA
Photos beat promises every time. Below are real transformations we’ve completed in Chino and nearby San Bernardino County neighborhoods, each with the written price, permit set, and photo record delivered under Haven Standard Clause 1. If you’re weighing whether an ADU makes sense on your property, here’s what actually happened on sites like yours.
Recent Transformations
Garage Conversion ADU: College Park Single-Car to 420-Square-Foot Studio
The homeowner needed rental income to offset a recent property tax reassessment. The existing slab was 4 inches, within range for a conversion per Chino Building Division’s residential code, but the setback from the alley measured 3 feet 8 inches - tighter than the 4-foot standard. We filed for a minor variance with a site plan showing fire-rated exterior sheathing, and got approval in 11 business days. The electrical service needed an upgrade from 100-amp to 200-amp to handle the ADU load plus the main house. We coordinated Southern California Edison’s meter spot and pulled the permit as a single application. Total project ran $127,000-$156,000 all-in, drawings through final inspection, with the written price locked at signing under Haven Standard Clause 1. The owner now rents it for $1,850 monthly.
New Detached ADU: Ontario Ranch-Adjacent Backyard, 640 Square Feet
This Chino site sits near the Ontario Ranch boundary where the water table runs higher in winter. We brought in a soils report that showed expansive clay to 18 inches, so the foundation design shifted from standard stem-wall to a post-tensioned slab - the extra cost was $8,400, named in the written quote before we broke ground, not after we hit dirt. The client wanted a one-bedroom layout with a covered porch facing the main house for grandkid visits. We specified James Hardie fiber-cement siding for fire resistance in this brush-adjacent zone, and coordinated the prefab wall panels through our single-contract model. The city required a fire sprinkler system due to the 640-square-foot threshold; we subbed that to a C-16 licensed contractor and managed it within the same fixed price. Final certificate of occupancy issued 7 months after permit submission. The photo record - 340 images across 22 site visits - went to the client as a downloadable folder, not a summary.
Junior ADU & Interior Conversion: Chino Hills Border, Attached to Main Residence
The owner, a retired teacher in the neighborhood near Chino Hills High School, wanted to house her mother without the full cost of a detached unit. California’s Junior ADU rules let us work within the existing footprint - no new foundation, no separate meter, no fire sprinklers. The catch: the space needed a kitchenette with cooking facilities, and the ceiling height cleared 7 feet 6 inches only after we dropped the ductwork into soffits. We ran a new 3/4-inch water line from the main house meter and tied into existing sewer with a backwater valve - Chino’s Public Works Department flagged this area for occasional sewer backup during heavy rains. The electrical was trickier. The 200-amp panel had one open slot; we installed a subpanel in the Junior ADU with a 60-amp feed, sufficient for the mini-fridge, induction cooktop, and wall heater. Because this stayed under 500 square feet and retained the shared wall, the permit path was simpler - no school fees, no parkland dedication. Written price: $67,000-$84,000. Done in 14 weeks.
ADU Site Prep & Utilities: The Shoppes at Chino Hills Adjacent, Sloped Lot
Not every job we do is the ADU itself. This client near The Shoppes at Chino Hills wanted to phase the work - handle the site prep and utilities now, build the unit in two years when rates settled. Smart move, and one we see more often in Chino’s newer developments where lots were graded for drainage, not for construction access. We brought in a geotechnical engineer who specified a segmental block retaining wall with geogrid reinforcement to 6 feet - the old timber wall was rotted at the footer and leaning 8 degrees. The sewer lateral required a 45-foot directional bore under the existing driveway to reach the city main at the street; we pulled the Encroachment Permit through Chino’s Public Works and scheduled the inspection 72 hours out. Electrical trenching ran 220 feet from the main panel to the pad, sized for 200-amp service with room to upgrade. The written price for this phase - $34,000-$41,000 - included the photo record of every footing pour and compaction test. When the client’s ready for the ADU, the site won’t trigger re-inspection of work we’ve already documented.
Prefab Modular ADU: Abodu One Model, Near Chino Airport
This client specifically asked for Abodu - they’d toured the Palo Alto showroom and wanted the One model’s 500-square-foot layout. Our role wasn’t to sell them on our carpentry; it was to coordinate the system within a single contract so they weren’t managing Abodu, a separate foundation contractor, and a separate utility hookup. The site constraints near Chino Airport were real: the delivery truck needed a 14-foot clear width, and we had 12. We worked with Abodu’s logistics team on a tilt-bed trailer with a smaller turning footprint, then brought in a telehandler instead of a full crane to set the module - the power lines at 18 feet ruled out boom clearance anyway. Foundation was a pier-and-grade-beam system, not slab-on-grade, because the client’s soils report showed fill to 4 feet in this former agricultural zone. We pulled the Type V residential permit through Chino Building, coordinated Abodu’s factory inspection schedule with the city’s required pre-cover framing inspection, and handled the final utility tie-ins. The written price - $198,000-$224,000 for the full package, including the pier foundation and the covered parking the client added mid-process under Clause 5’s change-order protocol (signed, priced, no surprises). Set day was 6 hours from truck arrival to weathered-in.
Garage Conversion ADU: Downtown Chino Historic District, Two-Car to One-Bedroom
Historic District work in Chino adds a layer most contractors don’t price for. The city’s Historic Preservation Commission reviews exterior alterations for compatibility - new windows had to match the 6-over-6 pattern, and we couldn’t replace the original board-and-batten siding, only repair it in place. We brought in a preservation carpenter for three days to splice new redwood where termites had tunneled the sill plate. The interior was standard conversion work: insulation, mini-split, kitchenette, 3/4 bath. But the Historic Commission’s review added 4 weeks to the permit timeline, which we told the client upfront based on our last Downtown Chino project - a garage conversion on 6th Street that took 19 days for HP Commission clearance. The written price reflected this: $134,000-$162,000, with a line item for preservation carpentry and a note that the timeline estimate assumed one round of HP Commission comments, not three. We got it in one. The photo record includes detail shots of every siding splice and window installation for the client’s own records and any future resale disclosure.
Want Results Like These?
Every project above started with a free estimate - written, line-itemed, and guaranteed under Haven Standard Clause 1. No “call for pricing,” no ballpark that shifts once work starts. Nadia Ellery and our team at Ellery ADU Studio Chino have designed, permitted, and built 900+ ADUs since 2015, and we bring the same single-contract accountability to every site in Chino, from College Park to the Historic District to the Ontario Ranch edge. Call (909) 323-1107 to schedule your free estimate, or bring us any written estimate you already have for a Free Second Opinion. A live person answers, 24/7.
Written by Nadia Ellery, Owner at Ellery ADU Studio Chino, serving Chino since 2015.