Fast, Reliable New Detached ADU Across Garland
A new detached ADU in Garland typically runs $185,000 to $320,000 all-in, drawings through final inspection, depending on square footage, site conditions, and whether you build custom or specify a prefab system. That is the real range we quote, in writing, before any work starts. No “call for a quote” here; the price is on the table at the first sit-down. Our design-build team serves Garland homeowners from the Firewheel area down through the historic districts west of downtown, and we coordinate every project from our Dallas-Fort Worth office with crews dispatched locally. If you want to talk numbers for your specific lot, call (971) 497-2402.
Why Ellery ADU Studio Is Garland’s Preferred New Detached ADU Company
What separates a good ADU from a dispute is the permit set. Most Garland projects we take over from other contractors stalled because the drawings did not account for what was actually behind the walls. We don’t guess. Ellery ADU Studio has designed, permitted, and built 900+ ADUs since 2015, and every single one carried a written price before work started under Haven Standard Clause 1. Homeowners in Garland call us because we say, in writing, what the foundation line item includes, what the panel upgrade costs, and what happens if the framing fails inspection. That is the documentation that protects a six-figure decision.
Our Garland clients get the same evidence we would want for ourselves: a documented photo record on every visit, a written scope that is locked at signing under Haven Standard Clause 5, and a 365-Day Done Right Promise that says if the finished ADU does not match the permitted drawings, we make it right. That promise is in writing before the first shovel turns. Nadia Ellery, who runs the studio, reviews every permit set that leaves our office for Garland jobs. Not a project manager. The person whose name is on the contract.
Our New Detached ADU Services in Garland
Our New Detached ADU team handles everything from a 400-square-foot studio behind a ranch home in Brentwood Place to a two-bedroom rental unit on a corner lot in Club Hill. Each of the services below is delivered as one contract, one written price, and one team accountable for the drawings, the permit set, and the build.
Custom Built ADU
When you build custom in Garland, you are working with a lot whose soil moves. The Blackland Prairie clay under most of the city shrinks in summer drought and swells after rain. A custom ADU foundation has to be engineered for that movement, not poured like a patio slab. We specify pier-and-beam or post-tension slabs with geotechnical review as standard on custom Garland builds. The building envelope gets the same treatment: Garland’s summers push attics past 140 degrees, so we size HVAC and insulation for a real Texas August, not a generic climate zone.
Prefab ADU Installation
Prefab systems from Abodu, Dvele, and Cover work well on Garland lots that have clear crane access from the alley or the street. We coordinate the factory order, the site prep, the foundation, and the utility tie-ins under the same contract, so you are not managing three vendors. One point that matters here: Garland’s alley-accessed lots often have narrow rear easements, and not every prefab module can make the turn. We verify the clear path before you commit to a system. That is the kind of check that saves $20,000 in revision work.
Modular ADU
Modular construction splits the difference between custom and prefab: panels and components built off-site, assembled on your foundation. For Garland homeowners who want design flexibility without an eight-month on-site build, this is the route we recommend most often. Modular also handles Garland’s clay soil well because you can engineer the foundation now and place modules later, without waiting on weather or trade sequencing. We have completed modular ADUs in the Springpark and Camelot areas, most with kitchens and full baths.
Studio ADU
A studio ADU in Garland, roughly 400 to 550 square feet, is the highest-rent-per-square-foot unit we build. The math works because Garland’s rental market has strong demand from single renters and young couples who want a private entrance but do not need two bedrooms. Our studio builds include a kitchenette, a full bath, and a separate meter where Garland’s utility rules require it. We also run the load calculation early; a studio with an induction cooktop and a mini-split can still push a 60-amp panel over the edge, and that upgrade belongs in the quote, not in a change order six weeks in.
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 Garland
We specify and coordinate prefab and modular systems from Abodu, Cover, Dvele, and Mighty Buildings. The difference for Garland customers is that we do not just hand you a factory brochure and wish you luck. We inspect the site for alley access and crane clearance, verify the foundation design against Garland’s clay soil, and coordinate the utility connections. When something goes wrong between the factory and the finish, you call one number, ours. Not three. That is the value of the single-contract model applied to factory-built homes.
Common New Detached ADU Problems We See in Garland Homes
- 60-amp panels that cannot carry an ADU load. Garland’s alley-garage ranch homes were wired in the 1960s when a garage needed lights and one outlet. Add a kitchenette, a mini-split, and laundry, and the math fails at rough-in inspection. We price the 200-amp upgrade in the contract, every time.
- Clay soil cracking new slabs. Garland sits on Blackland Prairie, and the clay expands and contracts enough to crack an unreinforced slab within two to three years. A geotechnical review is not optional for a new detached ADU here; it is the difference between a unit that lasts and one that fails.
- Termite-damaged framing hiding behind drywall. Older Garland ranch homes have decades of framing we cannot see until walls open. We write a framing allowance into the scope so termite repair does not become a mid-project fight.
- Failed waterproofing on existing garage slabs. Many 1950s and 1960s alley garages in Garland were poured without a moisture barrier. When you convert one to an ADU, the slab wicks water up into the floor and walls. We inspect for this before quoting and include the retrofit line item if needed.
Pricing for New Detached ADU in Garland, TX
Here are the ranges we quote in Garland for 2025 builds, all-in, drawings through final inspection:
- Studio ADU (400-550 sq ft): $185,000-$235,000
- 1-Bed ADU (550-750 sq ft): $225,000-$285,000
- 2-Bed ADU (750-1,000 sq ft): $270,000-$320,000
- Prefab/modular ADU (same sizes): comparable total cost, with savings concentrated in on-site labor time; the system cost runs $250-$400 per square foot depending on brand and finish level.
Two Garland-specific line items almost always appear: the $3,000-$5,000 service upgrade to 200 amps on homes with 60-100 amp panels, and the geotechnical review and foundation engineering required for clay soil, which runs $4,000-$8,000 depending on lot size and soil test results. Every quote we write includes these as fixed line items or written allowances before you sign. Call (971) 497-2402 for a written estimate on your specific Garland lot.
We Also Serve Cities Near Garland
Our crews serve Garland and the surrounding cities: Rowlett, Richardson, Mesquite, and Plano. The same team, the same written-price standard, the same 365-Day Done Right Promise applies whether your lot is in Garland’s Travis College Hill district or a Rowlett cul-de-sac one exit north on Highway 66.
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 - New Detached ADU in Garland
The short answer: if your home has a 60-amp or 100-amp main service, which describes most Garland alley-garage ranch homes built between 1955 and 1980, the 200-amp upgrade is effectively mandatory once you add an ADU’s HVAC, kitchen, and laundry load. The cost in Garland runs $3,000-$5,000, and we confirm it during pre-construction inspection before quoting. Call (971) 497-2402 and we will check your panel during the free estimate visit.
It genuinely matters. Garland’s clay soils expand and contract enough that unreinforced slabs crack within two to three years. We require a geotechnical review on every new detached ADU foundation in Garland and engineer the slab or pier system for the tested soil conditions. Skipping this step to save $4,000 turns into a $25,000 foundation repair later. We price it up front, in writing.
We inspect the existing structure (if converting an alley garage), the main electrical panel and service drop, the foundation and slab condition, the roof framing, the site drainage, and the alley or street access path for construction equipment. Every finding is documented with photos and included in your written quote as a fixed line item or a written allowance. You see the same photos we do. Call (971) 497-2402 to schedule the inspection; it is part of the free estimate.
Most 1960s alley garages in Garland can convert to an ADU without full demolition, assuming the foundation passes geotechnical review and the framing is sound. The permit will trigger several things: a load calculation that almost always requires the 200-amp service upgrade, structural review of the roof and wall framing against current code, and waterproofing requirements on the slab and exterior walls. We inspect for all of these before you commit, and the quote reflects them in writing.
We do not build on a cracked slab. For a Garland garage with no waterproofing and visible slab cracks, we remove the failed slab, compact and prepare the subgrade, install a proper vapor barrier, and pour a new engineered slab or install a pier system depending on the geotechnical report. This is a fixed line item in your written quote, not a surprise. You approve the number before demolition starts, and the 365-Day Done Right Promise covers the finished foundation. Call (971) 497-2402 for the written estimate.
Written by Nadia Ellery, Owner at Ellery ADU Studio. Our team has designed, permitted, and built 900+ ADUs since 2015, every one with a written price before work started.