Fast, Reliable Garage Conversion ADU Across Upland
Garage conversion ADUs in Upland typically run $85,000-$165,000 all-in, drawings through final inspection, with detached two-car garage conversions landing in the middle of that range and attached single-bay conversions at the lower end. We’re Ellery ADU Studio, and our Garage Conversion ADU team coordinates dispatch from our Inland Empire office with crews serving Upland directly. We’ve worked the 1950s-1970s ranch stock from south of the 10 freeway up through the north Upland parcels rising toward the mountains, and we know which conditions on your specific lot will move the number before we quote.
Call (840) 212-3065 to schedule your free estimate. Every project gets a written price before any work starts, per Haven Standard Clause 1.
Why Ellery ADU Studio Upland Is Upland’s Preferred Garage Conversion ADU Company
We’ve designed, permitted, and built more than 900 ADUs since 2015, the year California’s ADU laws shifted, and a significant share of those have been garage conversions in Upland and the surrounding Inland Empire. Our reviews from Upland customers consistently note the documented photo record we deliver on every visit - clients receive evidence of what was found and what was done, not a summary of how it felt.
Response time to Upland is same-day for initial site visits, with scheduling coordinated from our Inland Empire office. We know the local permitting pathway: Upland Building & Safety, not San Bernardino County, handles every ADU permit in city limits. That matters because county-drawn plans stall in Upland plan check, and we’ve seen owners lose six weeks to that mistake.
Our license number appears on every page, verified, not just claimed. Background-checked, uniformed crews. A live person answers calls 24/7 - no voicemail queue.
Our Garage Conversion ADU Services in Upland

Detached Garage Conversion
This is the most common conversion we do in Upland, and for good reason. The city’s 1950s-1970s subdivisions left an unusual concentration of deep lots with detached two-car garages set well behind the main house. On a deep-lot 1960s ranch off the north side of 19th Street, we converted a detached two-car garage into a one-bedroom ADU and immediately hit a base of 100-amp service feeding the house and the garage panel. Our tech pulled a new subpanel run and swapped the original galvanized supply stubs before insulation, then spec’d a right-sized ductless mini-split so the unit could hold through 105°F afternoons. The 5-10% grade behind the garage forced a short engineered retaining solution at the pad edge, which we scoped before quoting rather than after demo.
Detached conversions in Upland typically run $95,000-$165,000. The grade issue on north Upland parcels above 19th Street can add $8,000-$18,000 for engineered retaining or caissons. We find that in walk-through, not after you’ve signed.

Attached Garage Conversion
Attached garages in Upland’s ranch stock are usually single-bay or two-car structures sharing a wall with the main house. These conversions run $85,000-$135,000 and tend to move faster through plan check because the utility tie-ins are shorter runs. The catch: shared walls mean fire-rated assemblies and sometimes structural separation details that a detached garage avoids. We address those in the permit set, not as change orders mid-build.

Garage Partition & Bathroom Add
Some Upland owners want to keep vehicle storage and add a studio or bedroom-bath suite in the remaining footprint. This is a partition conversion, and it’s more common on the wider detached garages in the Foothill Knolls and San Antonio Heights areas. Pricing runs $75,000-$125,000 depending on whether we’re adding a full bath with sewer lateral work or a half-bath on existing drainage. The 1950s-1970s sewer laterals in clay or Orangeburg pipe are a routine find on these jobs, and we scope that replacement in the original quote.

Garage JADU
A Junior ADU, or JADU, is contained entirely within the existing garage footprint with no expansion beyond the walls. In Upland, this typically means a 400-500 square foot studio with kitchenette and separate entrance, running $65,000-$95,000. The owner must reside in either the main house or the JADU, a state requirement we document in the permit set. JADUs avoid some of the utility-separation complexity of full ADUs, but they still trigger the same wind-corridor framing requirements on any structural modification.

Carport Conversion
Less common in Upland than garage conversions, but present in some 1960s tracts. A carport-to-ADU conversion requires full enclosure, foundation work where there was only slab or dirt, and complete MEP rough-in. These run $110,000-$175,000 and take longer in plan check because the structural path from open carport to conditioned space is more complex.

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.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Upland
We specify and coordinate prefab and modular systems within our single-contract model, including Abodu, Cover, and Dvele units where the garage conversion scope includes a partial rebuild or where the existing structure is unsalvageable. For cladding and exterior finish on conventional stick-built conversions, we regularly source James Hardie fiber-cement products through our Inland Empire suppliers. Everything moves under one written price, one contract, one point of accountability - no designer-versus-builder gap.
Common Garage Conversion ADU Problems We See in Upland Homes

- Undersized electrical service. The 100-amp panels common in 1950s-1970s Upland ranches cannot carry a habitable ADU load. We find this on roughly half our garage conversion walk-throughs. Upgrading to 200-amp service and pulling a new subpanel run is a $4,500-$8,500 line item that must be in the original quote, not discovered after drywall is open.
- Aging sewer laterals in clay or Orangeburg pipe. Upland’s housing stock was built with materials that have reached end of life. A garage conversion with bathroom requires a sewer lateral that will pass pressure test. Replacement runs $3,500-$7,000 depending on length and depth to main.
- Wind-corridor framing requirements. Upland sits at the mouth of a recognized wind corridor funneling Santa Ana and Cajon Pass events off the San Gabriel Mountains. City plan check enforces higher Basic Wind Speed zones than default California standards. Roof-to-wall connections, sheathing nailing patterns, and hold-down details must be engineered accordingly. Plans drawn to generic wind loads get rejected.
- North Upland grade surprises. Parcels above 19th Street frequently carry 5-10% natural slope. Owners who priced the job against a flat south-Upland lot near the 10 freeway discover too late that their pad needs engineered retaining walls or drilled caissons. We survey grade on every walk-through and scope that work before quoting.
Pricing for Garage Conversion ADU in Upland, CA
| Conversion Type | Typical Range in Upland | Common Adders |
|---|---|---|
| Garage JADU (studio, existing footprint) | $65,000-$95,000 | Panel upgrade: $4,500-$8,500 |
| Attached Garage Conversion | $85,000-$135,000 | Sewer lateral: $3,500-$7,000 |
| Detached Garage Conversion, flat lot (south Upland) | $95,000-$140,000 | Retaining wall: $0 (flat lot) |
| Detached Garage Conversion, sloped lot (north Upland) | $105,000-$165,000 | Engineered retaining/caissons: $8,000-$18,000 |
| Garage Partition & Bathroom Add | $75,000-$125,000 | Bath rough-in scope dependent |
| Carport Conversion | $110,000-$175,000 | Full foundation + enclosure |
These ranges include design, permit set, all construction, and final inspection sign-off. Under Haven Standard Clause 1, the written price is locked before any work begins. No change orders for conditions we should have found in walk-through. Call (840) 212-3065 for your free estimate - we’ll walk the site, identify which of the above conditions apply to your property, and return a line-item written quote.
We Also Serve Cities Near Upland

Our crews work throughout the Inland Empire, including Garage Conversion ADU in Upland and surrounding cities: Rancho Cucamonga to the east, Montclair and Ontario to the south, and Pomona to the west. Each city carries its own permitting pathway - Pomona and Claremont run through LA County channels, while Upland remains exclusively city-permitted. We know which desk your plans land on.
Serving Upland, CA - Our Local Coverage Area
We’re based in the Upland 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 - Garage Conversion ADU in Upland

Upland Building & Safety is the only issuing authority for ADU permits within city limits. Plans drawn to San Bernardino County templates will stall in Upland plan check. We prepare permit sets specifically for Upland’s fee schedule, plan-check queue, and inspection sequence. Call (840) 212-3065 for a free estimate - we’ll confirm your parcel’s jurisdiction in the first walk-through.
North Upland parcels above 19th Street frequently sit on 5-10% natural grade toward the mountains, requiring engineered retaining walls or drilled caissons for the ADU pad. South Upland lots near the 10 are typically flat. That grade difference adds $8,000-$18,000 to foundation and sitework costs. We survey slope on every walk-through and scope retaining work before quoting, not after demo begins.
Upland’s position at the mouth of the Santa Ana/Cajon Pass wind corridor places much of the city in a higher Basic Wind Speed zone than default California standards. City plan check enforces specific sheathing nailing patterns, roof-to-wall connection hardware, and hold-down details on every garage conversion. Plans stamped to generic wind loads get rejected. Our permit sets are engineered for Upland’s actual zone. Call (840) 212-3065 to schedule a free estimate.
No. A habitable ADU requires sufficient electrical capacity for lighting, outlets, kitchen appliances, and HVAC. The 100-amp panels common in Upland’s 1950s-1970s housing stock cannot carry that load. We upgrade to 200-amp service and pull a new subpanel run as standard scope, priced at $4,500-$8,500 depending on trench length and utility coordination. This is scoped before quoting, never a surprise mid-project.
Yes. Upland summer highs regularly push past 105°F, and California habitability standards require heating and cooling. A right-sized ductless mini-split is essentially non-negotiable for any converted garage ADU here. We spec Mitsubishi, Daikin, or equivalent systems with load calculations based on the unit’s actual square footage, insulation values, and solar gain. The mini-split line item typically runs $3,500-$6,500 installed. Call (840) 212-3065 for an exact quote on your conversion - estimates are free.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Upland since 2015.