Fast, Reliable Garage Conversion ADU Across Arlington
Garage conversion ADUs in Arlington, TX typically run $145,000-$225,000 all-in, drawings through final inspection, with the spread driven by one local variable more than any other: whether your existing garage stays a garage. Arlington’s zoning code requires that a garage conversion either preserve your covered parking or replace it somewhere else on the lot, and that single rule moves more Arlington quotes than framing, finishes, or fixtures combined. Before you commit to converting, you need to know which side of that rule your property falls on. Ellery ADU Studio has walked hundreds of Arlington lots through this exact calculation, and we put the answer in writing before you spend a dollar. Call (971) 497-2402 to start.
Why Ellery ADU Studio Is Arlington’s Preferred Garage Conversion ADU Company
We are a design-build studio, which means the drawings, the permit set, and the construction are one contract at one written price. No designer points at the builder when a setback calculation misses, because there is no separate builder. Founded in 2015 and led by Nadia Ellery, our studio has designed, permitted, and built 900+ ADUs, every one quoted with a written price before work started. In Arlington, that matters more than in most markets, because the city’s accessory structure rules are specific enough that out-of-town contractors routinely submit plans that get denied on first review. Our team reads Arlington’s zoning ordinance before we measure a single wall.
Arlington homeowners who have worked with us consistently point to two things in their reviews: the permit set is thorough enough that the city has nothing left to flag, and the final invoice matches the written price. That second point is Clause 1 of The Haven Standard, our written project agreement: a written price before any work begins. Not a range. Not an estimate. A price. If something changes behind a wall, you approve the change order in writing before we touch it. That is how we work in every Arlington neighborhood, from Prestonwood Estates to Dalworthington Gardens.
Our Garage Conversion ADU Services in Arlington
Attached Garage Conversion
An attached garage conversion is the most common ADU path in Arlington for one simple reason: the city’s 1960s-1980s ranch housing stock came with attached one- and two-car garages as standard. The structure is already connected to your foundation, roof, and utility lines, so the conversion avoids the cost of trenching new service from the street. What it does not avoid is Arlington’s covered parking rule. If converting your attached garage eliminates your only covered parking, the city requires replacement covered parking elsewhere on the lot. In many cases, that means a carport addition or a detached garage, and that cost belongs in the quote from day one, not as a surprise after permit review. We include it, in writing, before you sign.
Detached Garage Conversion
Detached garage conversions are common in Arlington’s older platted subdivisions, where rear-lot garages were built decades ago and often sit on the irregular rear setbacks that make a straight conversion tricky. Arlington’s zoning code requires specific lot-coverage and setback calculations, and a detached garage that was built under older code may not legally convert without a variance. Here is the trade term: setback variance, the extra distance the city requires between your new ADU and the property line. We apply for the variance as part of the same permit package, so the city reviews one complete set, not a series of surprises.
Garage Partition & Bathroom Add
For Arlington homeowners who still need part of the garage for storage or a workshop, a partition conversion makes sense. We frame a dividing wall, add a bathroom, and convert one bay into a rentable or usable unit while the other bay stays a garage. Under Arlington’s covered parking rule, this can work in your favor: if the partitioned section leaves enough space for a vehicle, the city often counts it as preserved parking, and no replacement is required. We document the vehicle bay dimensions in the permit set so the city sees the parking preserved on paper.
Carport Conversion
Carport conversions in Arlington sit in a gray zone. A carport is covered parking, so converting it triggers the same replacement rule as a garage, but the existing structure rarely has the framing or foundation to become conditioned living space. Usually, we end up removing the carport and rebuilding as a detached ADU on a properly engineered foundation. For Arlington’s Blackland Prairie clay, that means piers or a post-tension slab, not a standard floating slab. We price that from the start.
What happens when you call
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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 Arlington
We specify and coordinate prefab and modular systems from brands including Cover, Dvele, and Boxabl within the same single contract. What that means for an Arlington garage conversion: if your existing slab is within range and the city’s coverage rule works in your favor, we can bring a prefab module onto the lot faster than a stick-built conversion would finish, with factory-controlled quality. If your site calls for a custom build, we build custom. The brand is not the point. The point is that the drawings, the permit set, and the installation are all ours to warrant under Clause 5 of The Haven Standard.
Common Garage Conversion ADU Problems We See in Arlington Homes
- Covered parking replacement denial. A contractor submits garage conversion plans without accounting for Arlington’s covered parking replacement rule. The permit gets denied days before demolition was scheduled, and the owner is stuck redesigning under pressure. We submit the parking plan with the initial permit set, never after.
- 100-amp panel overload. 1960s and 1970s Arlington homes were built with 100-amp electrical service. Add a second kitchen, bathroom, and HVAC load, and the inspector flags the panel. We run a scope-specific electrical load calculation before we touch the walls, and if the panel needs to go to 200 amps, that allowance is written into the contract on day one.
- Blackland Prairie foundation movement. Arlington sits on expansive black clay that swells in wet seasons and shrinks in drought. A slab that has moved for 50 years will show it once the walls come open. We always have a foundation specialist inspect before conversion work begins, and any pier or repair work gets priced and approved in writing before we proceed.
- Galvanized plumbing and undersized framing. Opening a 1960s Arlington garage wall often reveals galvanized plumbing long past its service life and framing that was never permitted. This is the single biggest reason a remodel quote moves. Our contracts carry a written contingency allowance for exactly this, so work does not halt while you renegotiate.
Pricing for Garage Conversion ADU in Arlington, TX
Here are real Arlington numbers, not national averages. An attached garage conversion to a one-bedroom ADU in Arlington typically runs $145,000-$185,000 all-in, drawings through final inspection. A detached garage conversion runs $175,000-$225,000, with the variance driven by foundation work on Blackland Prairie soil and the cost of running new utilities to a rear-lot structure. A garage partition with bathroom add runs $90,000-$130,000. A carport conversion, which usually means tear-down and rebuild, runs $130,000-$180,000. What moves these numbers: whether you preserve covered parking or replace it, whether your panel is 100-amp or 200-amp, and what the slab tells us when we open it. Every Ellery ADU Studio project is quoted with a written price before any work begins. Call (971) 497-2402 to schedule your free estimate and get your number.
We Also Serve Cities Near Arlington
Our Garage Conversion ADU team works throughout the Metroplex. If you are in Mansfield, Burleson, Cedar Hill, or Grand Prairie, we bring the same written-price contract, the same permit-set rigor, and the same local familiarity with North Texas soil and code. Garage Conversion ADU in Arlington is our home market, and the surrounding cities share the same North Texas building conditions, so our pricing and process travel well.
Serving Arlington, TX - Our Local Coverage Area
We’re based in the Arlington 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 Arlington
Arlington’s zoning code requires that covered parking be preserved or replaced when a garage is converted. If the conversion eliminates your covered parking, the city will likely require you to build a replacement carport or garage elsewhere on the lot before the permit is approved. A driveway spot does not satisfy the requirement. We document this during the initial site visit and include any replacement parking in your written price, so there is no post-permit surprise. Call (971) 497-2402 to have us check your lot against the current code.
No, it does not automatically force an upgrade, but in practice most Arlington garage conversions from that era do require one. The issue is load calculation: a new ADU adds a kitchen, bathroom, and HVAC demand that a 100-amp panel was never sized for. We run the calculation during design, not after the inspector flags it. If the upgrade to 200 amps is needed, it is written into your contract as a line item before work starts, and we do not reopen finished walls to run it later. Call (971) 497-2402 for a written load calculation and price.
For an attached garage conversion, the clay matters less structurally, because the garage slab was typically poured as part of the original home foundation and has moved with the house for decades. For a detached ADU or a rear-lot garage conversion, the clay matters a lot: we specify engineered piers or a post-tension slab designed for shrink-swell soil, and that adds real cost. In some older Prestonwood Estates homes, we have also seen the clay movement crack garage slabs at the corner where drainage concentrated. We bring in a foundation specialist before we design, and the inspection is part of the estimate process.
Expect undersized framing that was never permitted, galvanized plumbing past its service life, and waterproofing that was never installed to conditioned-space standards. Garages built in the 1960s were not designed to be lived in, so the wall cavities often lack insulation, the sill plate may not be pressure-treated, and the slab edge may not have a proper moisture barrier. We open the walls as part of our inspection, document what we find with photos, and price any corrections as written change orders before we proceed. You approve every dollar before it is spent.
Arlington’s short-term rental ordinance applies to any dwelling unit rented for less than 30 consecutive days, and that includes an ADU. The city requires registration and collection of hotel occupancy tax. A long-term rental, 30 days or more, is governed by standard residential tenancy rules instead. Both are permitted uses for an ADU once the unit is permitted and built to code, but the short-term path has a registration step that the long-term path does not. We do not handle your rental registration, but we do build the unit to the code standard that makes either path legal. Call (971) 497-2402 to talk through how your intended use shapes the design.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Arlington with written-price ADU design and construction since 2015.