







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Garage Conversion Contractor Across Covina
A garage conversion in Covina typically costs between $85,000 and $145,000 for a full ADU with kitchen and bath, and $45,000 to $85,000 for a simpler garage-to-bedroom or living-space conversion before permit fees. That’s the honest range we quote and the range we build to. If you live off Badillo Street, up in Covina Hills, or in the Charter Oak neighborhood, you already know Covina isn’t like flat West Covina or Baldwin Park. The slopes, the clay soil, the oak trees, and the city’s drainage review all shape what your conversion costs and how long it takes. Our crews work Covina every week. We know which inspectors look for what, and we price that in writing before you sign anything. Call (559) 238-9583 for a free estimate.
Why Fielding ADU West Covina Is Covina’s Preferred Garage Conversion Contractor Company

Covina homeowners don’t need a contractor who guesses. They need one who has already pulled permits at City Hall on College Street, who knows that Charter Oak drainage reviews run stricter than anywhere else in the San Gabriel Valley, and who has stood in front of the Planning Commission explaining an oak tree setback. That’s us.
Reed Calloway leads our team, and he built Fielding ADU West Covina inside the Garrison Partners family, which has been building to The Garrison Standard since 2006. The Garrison Code is five things, none of them negotiable: show up in the window, price in writing, build by the book, leave the site clean, stand behind it for a year. Every job we do in Covina carries a written 365-day guarantee. If something fails in that year, we return at no charge. Call (559) 238-9583 and a live person answers. Not a queue. Not a voicemail. Day or night.
Our crews arrive in uniform, background-checked, and they know the difference between a Covina Hills hillside lot and a Charter Oak flood-channel slope. That local knowledge isn’t a talking point. It’s the reason your foundation doesn’t settle, your drainage passes first inspection, and your final invoice matches the first number we put in front of you.
Garage to Bedroom Conversion in Covina
A garage to bedroom conversion in Covina turns an underused 1950s or 1960s detached garage into a comfortable sleeping room, home office, or guest suite, and it’s the right move when you don’t need a full kitchen or separate address. On a flat lot in central Covina, a garage to bedroom conversion typically runs $45,000 to $85,000 before permit fees. The work involves insulating and drywalling the original shell, running electrical from the main panel, adding egress windows, and often upgrading that undersized 100-amp panel that so many Covina ranch homes still have.
Foundation and Drainage Work
Older Covina garages sit on slabs poured before anyone cared about soil expansion. On the clay-heavy foothill lots south of Badillo and along Covina Hills Road, that matters. We test the soil, and when the report says expansive clay, we design the slab or stem wall to move with it, not against it. A cheap bid skips the soil report. Covina inspectors don’t.
The Permit Path in Covina
A garage to bedroom conversion in Covina requires a building permit, and depending on your lot, a drainage review. We pull every permit, schedule every inspection, and keep a clean job file so the building department sees a trail of compliance from day one. You’re not guessing what got inspected. You have paper for all of it.
Garage Conversion ADU in Covina

A garage conversion ADU in Covina is a full dwelling unit with its own kitchen, bath, bedroom, and entrance, and it’s the highest-value use of an existing detached garage in Covina’s R-1 neighborhoods. A complete garage ADU in Covina typically runs $85,000 to $145,000 before permit fees, depending on whether you need a new foundation, electrical panel upgrade, or drainage engineering. These units work well for rental income, aging parents, or adult kids who can’t afford a starter home in Covina right now.
Drainage on Sloped Lots
If your garage sits on a slope that runs toward one of the concrete flood channels, like many properties off Charter Oak Road, the city will require engineered retaining walls and swales before they sign off. We design for that from the first site visit, not as a change order later. The Garrison Standard means the number we quote is the number you pay.
Prefab or Conventional Build
Some Covina homeowners choose a conventional stick-built ADU. Others want a Plant Prefab or Abodu panelized system delivered and set on the existing slab. We’ll talk through both honestly, because the right answer depends on your lot, your budget, and how fast you need occupancy. We have built both in Covina and we can show you a written price for each path before you commit.
Trusted Brands We Service in Covina
If you’re researching garage conversion options, you’ve probably come across Plant Prefab, Abodu, Tuff Shed structures, and James Hardie siding. We work with all of them. For Covina specifically, we keep a steady supply of James Hardie fiber-cement lap siding and HardieBacker board in stock because so many of our Covina projects require 110 mph exposure C wind ratings that cheaper siding doesn’t carry. When you call for a quote, tell us which brand you’re leaning toward. We’ll price it honestly and tell you if a different material will serve your house better in Covina’s wind and drainage environment.
Common Garage Conversion Contractor Problems We See in Covina Homes
- Undersized electrical panels. Most 1950s and 1960s Covina ranch homes still have a 100-amp panel. A garage ADU with a kitchen and mini-split HVAC pulls more than that. We include the panel upgrade in the written price, so you’re not surprised mid-project.
- Concrete slabs poured without a soil expansion report. Covina’s foothill lots sit on clay that swells with winter rain and shrinks in summer heat. A new slab poured on that soil without engineering will move. We see hairline cracks turn into structural problems within two rainy seasons.
- Original garage roof framing reused on an ADU. Covina enforces a 110 mph exposure C uplift requirement. A 1960s garage roof with toenailed rafters doesn’t meet it, especially on east-west ridgelines where Santa Ana winds hit hardest. Reinforcing that roof is a line item we always include. Cheap bids leave it out and pray for a calm winter.
- Missing lateral bracing on old garage walls. If the original garage walls were never shear-paneled, a Covina inspector will red-tag the project. We add structural sheathing and anchor bolts at the required spacing before any interior work starts, so the inspection passes the first time.
Pricing for Garage Conversion Contractor in Covina, CA
Here are the numbers, in writing, the way we quote them in Covina. A garage to bedroom or living space conversion runs $45,000 to $85,000. A full garage conversion ADU runs $85,000 to $145,000. Permit fees run separate and are set by the City of Covina, usually $4,000 to $9,000 depending on scope. A panel upgrade adds $3,500 to $6,000. Drainage engineering on a sloped Charter Oak lot adds $8,000 to $20,000 depending on retaining wall height and swale length. Every quote from Fielding ADU West Covina shows these as line items on paper before work starts. Call (559) 238-9583 and Reed or his team will give you a written breakdown specific to your Covina lot.
We Also Serve Cities Near Covina
Fielding ADU West Covina serves Covina and the surrounding San Gabriel Valley. Our crews regularly work in Covina, West Covina, Baldwin Park, Walnut, and Hacienda Heights. If you’re one city over and your lot runs into similar drainage review or wind-load requirements, the same Garage Conversion Contractor team handles it the same way: written price first, by-the-book build, and a full-year guarantee.
Serving Covina, CA - Our Local Coverage Area
We’re based in the Covina 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 About Garage Conversion Contractor in Covina
Covina enforces a 110 mph exposure C wind-load requirement for garage conversion ADUs, which means the roof framing, wall sheathing, and anchor bolt spacing all have to meet that standard in the design and pass inspection. Our quotes include the structural reinforcement line items that meet that rating, and the engineering documentation that proves it. Call (559) 238-9583 for a written quote with the wind-load compliance spelled out.
If your lot slopes toward one of Covina’s concrete flood channels, you very likely need an engineered retaining wall and a drainage swale before the city signs off on a garage conversion. The Charter Oak drainage review is one of the strictest in the San Gabriel Valley, and we design for it from the first site visit, not as a change order later. Call (559) 238-9583 and we’ll walk the slope with you and tell you what the inspector will look for.
Documented wind-load compliance with photos, engineering letters, and inspection sign-offs gives your insurance carrier proof that the structure met Covina’s 110 mph exposure C standard, and in many cases that means the difference between a denied claim and a paid claim after a Santa Ana wind event. We build and document to that standard on every Covina garage conversion because the paper trail is half the asset.
Most Covina homes built in the 1950s and 1960s have a 100-amp panel, and a garage conversion ADU with a kitchen, mini-split HVAC, and electric water heater typically needs a 200-amp panel upgrade. That’s a $3,500 to $6,000 line item we include in our written price. If your panel already has capacity, we’ll tell you that too, and you won’t pay for an upgrade you don’t need.
You can, but Covina’s oak tree preservation rules apply if a protected oak sits within the setback or drip line of the garage you want to convert, and you may need an arborist report and a design that keeps the foundation away from the root zone. We’ve converted several detached garages in Covina Hills under oak canopies, and we’ll flag the tree issue on the first visit so the permit path is clear from the beginning. Call (559) 238-9583 for a free estimate.
Written by Reed Calloway, Owner at Fielding ADU West Covina, serving Covina homeowners as part of the Garrison Partners family since 2006.




