Fast, Reliable Garage Conversion ADU Across Garland
Garage conversion ADUs in Garland typically run $125,000 to $185,000 all-in, from structural evaluation through final inspection, with the exact number driven by electrical service upgrades, foundation work on Blackland Prairie clay, and whether your detached garage sits on a rear alley slab built before the 1980s code changes. That written price is locked before any work starts, per Haven Standard Clause 1. If you’re weighing a garage conversion as rental income, a multigenerational living arrangement, or a long-term asset, call us at (971) 497-2402 and we’ll walk the property with you, document what’s actually there, and hand you a scope of work with a dollar figure attached.

Why Ellery ADU Studio Is Garland’s Preferred Garage Conversion ADU Company
Nadia Ellery founded this studio in 2015 to close the gap between what a designer draws and what a builder charges. We operate as a single design-build contract in Garland: the permit set, the engineering, and the construction are one written price, not three competing invoices. That matters in a city where most ranch homes from the 1950s through 1970s carry structural conditions that architects in other markets never see.
We’ve completed over 900 ADUs since founding, and the ones in Garland share a pattern. Rear alley garages with cracked slabs. 60-amp panels that were fine for lights and a garage door opener but can’t handle a mini-split, a kitchenette, and a washer. Lots that slope toward the alley, not toward the street. Our crews are dispatched from our Dallas-Fort Worth office and serve Garland neighborhoods directly, so the person who scopes your project is the same team that pulls the permit and frames the walls.
Every Garland project gets a documented photo record on each visit. You’ll see what we found under the slab, what the panel looked like before and after, and what the foundation piers looked like when we set them. That’s the Haven Standard, Clause 4: evidence, not a summary.
Our Garage Conversion ADU Services in Garland

Detached Garage Conversion
Garland’s dominant housing stock is single-story brick-veneer ranch on concrete slab, and a large share of those homes have detached garages accessed via rear alleys. That’s the single most ADU-ready structure in residential construction: a separate footprint, its own roof, and alley-grade access already in place. But the slab under that detached garage was poured decades before Garland’s 1980s code required footings sized for Blackland Prairie clay movement. Nearly every conversion in central and west Garland starts with structural evaluation for slab movement and pier alignment before we’ll commit to a framing start date. We quote that evaluation as a line item, not a surprise.

Garage Partition & Bathroom Add
Some Garland homeowners don’t need a full ADU. They need a bedroom with a private bath for an aging parent or an adult child, built inside an existing attached garage footprint. This service typically runs $55,000 to $85,000 depending on the plumbing run and whether the existing slab can accept a new bathroom without cutting the foundation. In neighborhoods like Camelot and Spring Park, where attached garages share the main slab, the plumbing geometry often drives the quote more than the room count.

Garage JADU
A Junior ADU carved from an existing detached garage gives you flexibility: a compact living space under 500 square feet, small kitchenette, and a bath. Texas law doesn’t use California’s JADU label, but the structure works the same under Garland’s accessory dwelling rules. This is the lowest-cost path to rentable square footage, typically $70,000 to $95,000, and we often pair it with a main-house renovation already on the drawing board.

Carport Conversion
Carport-to-ADU conversions in Garland are rarer than garage work, but they’re feasible when the carport is already covered and framed on three sides. The catch: a carport slab was rarely engineered for a living space, so you’re usually pouring a new slab or installing perimeter footings. If the carport sits on the rear property line near a county septic system or a private well on the open-lot side of Garland, setbacks become part of the quote before we ever submit drawings. Homes off East I-30 and near Lake Ray Hubbard’s eastern edge often fall into this category.

What happens when you call
- 1
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 Garland
Ellery ADU Studio specifies and coordinates prefab and modular systems from Abodu, Cover, Dvele, and Mighty Buildings, among others. For a detached garage conversion in Garland, a prefab shell can shorten framing time by three to five weeks, but only if the existing slab passes the foundation review. Our team stocks the panel upgrade components, mini-split linesets, and sewer connections commonly needed on Garland’s alley-garage ranches, so we’re not waiting on a distributor in another county when your schedule matters. We’ll show you the spec sheets from whichever brand fits your lot and your budget, and every brand we recommend is covered under the same written warranty that governs the rest of the project.
Common Garage Conversion ADU Problems We See in Garland Homes

- Skipping the geotechnical review. Garland sits on expansive Blackland Prairie clay that shrinks in summer drought and swells after a rain. Any new detached ADU slab or addition foundation must be engineered for that movement. Homeowners who skip the review routinely see cracking within two to three years – and then call us to fix a problem that should have been designed out at the start.
- Quoting without checking septic and well setbacks. Parts of Garland, especially along the eastern and southern edges toward Lake Ray Hubbard, are on county septic systems and private wells. A Garage Conversion ADU on one of those lots can trigger a $15,000 to $25,000 extension or setback variance if the plumbing doesn’t clear the required distances. We verify this before quoting, not after the dig starts.
- Underestimating alley access for heavy equipment. Many of Garland’s rear-alley garages sit behind long, unpaved drive lanes. A concrete truck needs a stable, wide approach to pour a new slab or footer. If the alley can’t take the truck, we plan for a pumper or a hand-placement method and quote the equipment accordingly. Otherwise your framing crew is standing around mid-project while the concrete hardens in the wrong place.
- The 60-amp panel problem. Garland’s 1950s and 1960s ranch homes were wired for a different era. A converted ADU with HVAC, a kitchenette, and laundry almost always requires a 200-amp service upgrade at $3,000 to $5,000. Contractors who quote the ADU without that upgrade will stall at rough-in inspection. We include it in the written price, every time.
Pricing for Garage Conversion ADU in Garland, TX
Here are honest dollar ranges for Garland’s market, as of current material and labor costs:

| Detached garage conversion (full ADU, 400-600 sq ft) | $125,000 - $185,000 |
| Garage partition & bathroom add (150-250 sq ft) | $55,000 - $85,000 |
| Garage JADU (under 500 sq ft) | $70,000 - $95,000 |
| Electrical service upgrade (60/100 amp to 200 amp) | $3,000 - $5,000 |
| Foundation piers / slab stabilization for clay movement | $4,500 - $12,000 |
| Septic or well setback variance work | $15,000 - $25,000 |
What moves the number: soil conditions (we test, we don’t guess), distance from the existing sewer line, whether the garage shares a wall with the house or stands alone, and whether your property is on city sewer or county septic. Every quote is a written, line-item price before any work begins. That’s Haven Standard Clause 1, and it’s the reason we don’t say “call for a quote” – we say “here’s the number.” Call (971) 497-2402 for your written estimate.
We Also Serve Cities Near Garland

Our crews from the Dallas-Fort Worth office serve Garland and the surrounding communities: Rowlett, Richardson, Mesquite, and Plano. Many of those cities have attached garages on the main slab, so the pre-conversion foundation work differs from what we see on Garland’s detached alley garages. The Garage Conversion ADU process we run is the same written-price, one-contract model across the metro, but the local conditions change how we scope the job.
Serving Garland, TX - Our Local Coverage Area
We’re based in the Garland 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 Garland

Yes, and which authority issues them depends on your property. Most Garland addresses inside city limits pull permits from the City of Garland’s Building Inspection department. But if your property sits on the edges of the city toward Lake Ray Hubbard’s eastern shore or along the southern boundary, it may fall under unincorporated Dallas County permitting. We determine this before quoting so your written price reflects the correct permit path, including any septic or well clearance reviews. Call (971) 497-2402 and we’ll confirm your jurisdiction on the first visit.
Almost never without evaluation, and often not without repair. Garage slabs from that era were poured as a single flat pad, usually 4 inches thick, with no footings sized for the plumbing runs a bathroom and kitchen require. Garland’s clay soil compounds this: movement over decades cracks and shifts the pad. We test the slab, determine whether piers are needed, and quote that as a line item. If you skip this step, you’ll find out at rough-in inspection. Call (971) 497-2402 for a slab evaluation and a written number.
Yes, in most cases, but the structure below it has to carry the load. A second-story ADU above a detached garage on the rear property line means new lateral engineering, a taller foundation wall, and potentially a setback variance depending on your specific lot dimensions. The single-story garage slab wasn’t designed for two floors of living space, so you’re typically looking at new footings and shear walls. We scope that before quoting and include the variance paperwork in the written price. Call (971) 497-2402 to discuss your specific lot.
Because a light fixture and a door opener run on a 15-amp circuit, and an ADU with a mini-split, kitchenette, and laundry requires a 200-amp service. Garland’s ranch homes from the 1960s were built with 60 to 100-amp mains. That $3,000 to $5,000 line item is the panel replacement and new subpanel run to the garage. If your contractor’s quote doesn’t include it, you’ll discover it at rough-in when the inspector flags the load calculation. We include it in the written price because we’ve seen too many Garland projects stall at that exact moment. Call (971) 497-2402 if you want a quote that doesn’t hide this line.
Flatwork and grading on a rear-sloping lot is different from a street-sloping lot, and most Garland alley-garage ranches shed water toward the alley, not toward the street. We survey the lot, mark the high and low points, and design the ADU’s finished floor elevation so water moves away from the slab, not under it. If the alley is unpaved and carries runoff, we may need a French drain or a swale along the property line, and we quote that before digging. Call (971) 497-2402 for a site walk and a written drainage plan.
What Garland Homeowners Should Know Before They Sign Anything
Garland’s alley-accessed detached garages were built before the city’s 1980s building code required footings sized for Blackland Prairie clay movement. That means the structure you’re looking at was never engineered for the soil it’s sitting on. Nearly every conversion needs structural evaluation for slab movement and pier alignment before framing can start. This is not true in Plano or Richardson, where most garages are attached to the main slab and share the house’s foundation. It’s a Garland-specific condition, and it changes both the scope and the price.
Combine that with Garland’s large multigenerational Hispanic households actively seeking in-law quarters, and you have a convergence no neighboring suburb matches: ready-made detached structures, a cleared legal path under Texas HB 1415 (effective September 2023), and real cultural demand. We’ve converted a 1964 ranch off Belt Line Road near Duck Creek into a two-bedroom ADU for a multigenerational family. Our crew replaced the original 60-amp panel with a 200-amp service, installed a dedicated mini-split and a small kitchenette, then tied the new sewer line to the county septic system after confirming the well setback. The project passed Garland’s inspection on the first visit because we scoped the electrical and foundation work before quoting. That’s the standard we hold on every project in this city.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Garland homeowners since 2015.