A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateTrusted ADU Builders for Austin Homeowners
Working with Austin ADU Builders means navigating city code, lot setbacks, utility connections, and a permitting process that changed again this year. The homeowners who call us have usually already talked to a contractor who made promises and then went quiet. Fielding ADU Austin is an independently owned member of the Garrison Partners family, founded in 2006 and led by Reed Calloway. Every project we build gets a written price before work starts and a written one-year guarantee when it’s done. If you’re researching ADU costs or trying to figure out whether your lot can even hold one, call (361) 309-9568 and we’ll walk you through it.
Key Takeaways
- Detached ADUs in Austin typically run $180,000 to $390,000 depending on size, site work, and finish level.
- Garage conversions (a common JADU path) start around $90,000 to $150,000 before permit fees.
- We work with Abodu, Cover, and Tuff Shed platforms, plus conventional James Hardie builds.
- Written price before work starts. Written one-year guarantee after. No exceptions.
- Reed Calloway leads every Austin project. Live person answers the phone 24/7 at (361) 309-9568.
ADU Construction
ADU Construction means building a secondary dwelling unit on a residential lot that already has a primary home. In Austin, that usually means either converting an existing structure (garage, workshop) or building new square footage in the backyard. What we do at Fielding ADU Austin is handle the whole thing under one written price: site evaluation, plans, permits, foundation, framing, mechanical systems, finishes, and final inspection. A garage conversion in Austin typically runs $90,000 to $150,000 before permit fees; a new detached unit runs $180,000 to $390,000 depending on size and site conditions. The city’s impervious cover rules and tree ordinance can add cost before a single wall goes up, so we price those in writing on the front end.
Site Evaluation and Feasibility
Before any plan is drawn, we walk the lot and check what the city will actually allow. Setback variance (the city’s written permission to build closer to the property line than the standard rule allows) is sometimes required in older Austin neighborhoods where lots are narrow. We check drainage, access for equipment, and utility tie-in locations so the number you approve reflects what will actually happen.
Permit Handling
We pull every permit ourselves and schedule every inspection. Austin’s Residential Plan Review can take weeks depending on project complexity, and a missed detail sends you back to the end of the line. That’s the kind of delay that separates a real ADU contractor from someone who hands you a bid and disappears.
Detached ADU
A Detached ADU is a standalone structure built separately from your primary home, typically 400 to 1,100 square feet. Homeowners choose this route when they want a true rental unit, a private space for aging parents, or a quiet home office with a door that actually closes. Fielding ADU Austin builds detached units both ways: prefab and modular through partners like Abodu and Cover, or conventional stick-built with James Hardie siding. A detached ADU in Austin will run $180,000 to $390,000 depending on size, finish level, and how much site work your lot requires. Sloped lots in areas like Lago Vista add foundation cost; flat lots in Hutto or ADU Builders in Manor cost less to prep.
Prefab vs. Conventional Build
Prefab units from Abodu or Cover can shorten on-site construction time substantially because the structure is built in a factory. But prefab still requires an Austin foundation permit, utility trenching, and final inspection. Conventional building gives you full control over layout and finishes but ties up the yard longer.
Site Work and Utilities
The driveway, the trench for water and sewer, the electrical panel upgrade if your existing panel is undersized: these are the costs that catch people off guard. We quote them in the written price. No change orders at the door when the trencher shows up.
JADU
A JADU (Junior Accessory Dwelling Unit) is a smaller unit created within the footprint of an existing home, typically 500 square feet or less, with its own entrance, kitchenette, and sometimes a shared bathroom. Austin homeowners use JADUs to turn a garage or a basement-level bonus room into rentable space without building an entirely new structure. Fielding ADU Austin handles JADU conversions as part of its larger ADU Builders in Austin service. A garage JADU in Austin typically runs $90,000 to $150,000 before permit fees, depending on whether the existing slab, walls, and electrical can be reused or need to be rebuilt.
Garage Conversions
Most JADUs in Austin start as garages. The slab may be uninsulated, the walls may not be rated for living space, and the electrical panel often needs upgrading. We inspect all of it and put the real number in writing, including what can stay and what has to go.
Interior Access and Separation
The city requires a separate entrance for a JADU, and that changes how the existing floor plan works. We handle the door placement, the fire separation, and the sound isolation so the unit works as a rental without turning your whole house into a shared hallway.
ADU Plans
ADU Plans are the architectural and engineering drawings the City of Austin requires before a permit can be issued. They include site plans, floor plans, elevations, structural details, and mechanical/electrical layouts. Fielding ADU Austin prepares or coordinates these plans on every project, and the plan cost is folded into your written price. Plan preparation for an Austin ADU typically adds $5,000 to $15,000 to the project depending on complexity and whether you choose a custom design or a pre-engineered platform like Cover. The plans are what the permit reviewer reads, and a vague plan is why so many Austin ADUs stall in review.
Pre-Engineered vs. Custom Plans
Brands like Abodu and Cover arrive with engineered details already done, which can shorten permit review. Custom plans give you more freedom on layout and orientation but take longer to draft and review. We price both honestly and tell you which one actually fits your lot.
What Plans Include
The site plan shows setbacks, impervious cover, and tree locations. The structural sheets show foundation, framing, and roof. The mechanical sheets show the HVAC path, the electrical load, and the water line routing. If any of it is missing, the reviewer returns it without approval.
ADU Contractor
An ADU Contractor is the licensed builder responsible for taking an ADU from permit through final inspection. You don’t need a designer and a builder and a separate site-work crew if you hire one company that carries the whole thing. Fielding ADU Austin functions as your single ADU Contractor on every job: we handle the plans, pull the permits, run the crew, and pass the inspections. Our price goes in writing before any work starts, and the number you approve on day one is the number on the final invoice.
One Crew, One Schedule
Subcontractors who aren’t coordinated are the main reason Austin ADUs run months past schedule. Our crews are background-checked and uniformed, and the schedule is managed by Reed Calloway, not passed off to a rotating project manager. You’ll know who is on your property and when.
Written Guarantee
The Garrison Standard covers workmanship defects for 365 days. If something fails inside that year, we return at no charge and correct it. That guarantee is spelled out on paper, along with exactly how we make it right.
ADU Design
ADU Design is the process of laying out the unit’s footprint, room configuration, entry location, window placement, and interior finish level before plans are drawn. Good design on an Austin lot means fitting the unit into the existing yard without destroying the outdoor space you already use. Fielding ADU Austin handles design in-house, including when you want to work with a Tuff Shed-style structure or a full James Hardie exterior. Design work is included in your written project price, not billed as a separate surprise line item later.
Working With Existing Conditions
The slope, the trees, the fence line, the neighbor’s second-story window: these are design constraints in Austin, not afterthoughts. We design around what’s actually there so the unit fits the lot without needing variances you probably won’t get.
Interior Layout and Rentability
For a rental unit, the layout needs a private entrance, a functional kitchenette, and a bathroom that doesn’t walk through the bedroom. For a family member, you may want wider doors and a curbless shower. We design for how you’ll actually use it.
Backyard ADU
A Backyard ADU is a detached secondary home built in the rear yard of your property. This is the most common path for Austin homeowners who want rental income, because it changes the primary residence the least. Fielding ADU Austin has built backyard units across Austin, Georgetown, ADU Builders - Pflugerville, and the surrounding areas, using both conventional framing and prefab platforms like Abodu. Expect $180,000 to $390,000 for a completed backyard ADU in Austin depending on size, finishes, and how much utility trenching and site prep your lot demands.
Lot Constraints in Austin Neighborhoods
In neighborhoods like Wells Branch and Brushy Creek, the lots are large enough for a standard backyard unit with room to spare. In central Austin and older areas near Hornsby Bend, the lot may push right up against the setback line. We measure before we quote, so the price reflects the actual buildable footprint.
Utility Runs and Access
The water, sewer, and electrical line from the house to the backyard unit is measured in linear feet, and the trench has to be dug, inspected, and backfilled. If your electrical panel is at 100 amps and the unit needs 60 more, that means a panel upgrade. All of it goes in the written price on day one.
Brands We Service
We build and install Abodu units across the Austin area, which means we’re familiar with their foundation requirements, their utility stub-out locations, and what their factory finish includes before your local drywall and paint work begins. Their units arrive in a set number of modules, and the site prep has to be exact for the crane or truck delivery to work on day one. That’s the part most contractors get wrong and we get right.
Cover and Tuff Shed structures come with their own technical details too. Cover’s panelized system requires precise slab tolerances and careful sequencing for the local mechanical work that follows. Tuff Shed-style structures are simpler, but turning one into habitable space under Austin code still means insulation, electrical, plumbing, and a proper foundation, not a set of skids on gravel. Whether you have an Abodu, a Cover unit, a Tuff Shed, or a conventional James Hardie build, we can help.
Signs You Need a Pro Right Now
- Your contractor stopped answering after the deposit. Austin’s building boom means some crews take on more work than they can schedule. If your permit has been sitting in review for months with no movement, a real ADU contractor can take over and push it through.
- Your lot has a setback issue and nobody told you. If the plans you paid for don’t account for the city’s required distance from the property line, you’re looking at a variance or a redesign. A pro checks this before you spend a dollar on plans.
- The price on your bid is drifting upward without a written change order. Austin homeowners get hit with “unforeseen conditions” after demo starts. A written price before any work starts is the only defense against that.
- Your garage conversion keeps getting quoted as “maybe” when you ask about the slab. A garage slab without insulation or a vapor barrier won’t pass as living space. The fix costs real money, and a pro says so upfront instead of hoping you won’t ask.
- You’re not sure if your electrical panel can handle another unit. A 100-amp panel won’t carry a 400-square-foot ADU with a mini-split and an electric water heater. The panel upgrade is a line item, not a surprise. A pro puts it in the bid.
Our Process, Step by Step
- 1
Phone consult and site walk. Call (361) 309-9568 and we’ll talk through what you want to build, what your lot looks like, and whether your project is even possible under current Austin code. This is free and takes about 20 minutes.
- 2
Written feasibility review. We measure the lot, check setbacks, tree locations, and utility access, and tell you what can actually be built. You get a document, not a verbal estimate.
- 3
Written price and scope. The full price goes in writing before any work starts. This includes plans, permits, site work, construction, finishes, and the one-year Garrison Standard guarantee. No change orders unless you change the scope.
- 4
Permit submission and construction. We pull every permit and schedule every inspection. The crew is background-checked and uniformed. Reed Calloway runs the schedule and you’ll have his direct line the whole time.
- 5
Final walkthrough and written guarantee. We walk the finished unit with you, run every system, and hand you the one-year guarantee in writing. If something fails inside that year, we come back and fix it at no charge.
How Much Does ADU Builders Cost in Austin?
A typical garage conversion ADU in Austin runs $90,000 to $150,000 before permit fees. A new detached backyard ADU runs $180,000 to $390,000 depending on square footage, finish level, and site conditions. A JADU carved out of existing interior space runs $70,000 to $130,000. These numbers reflect what we’ve actually billed on Austin projects, not a national average pulled from a website.
What affects the price most is site work: the trench for utilities, the foundation type your soil requires, the electrical panel upgrade if your existing panel is undersized, and any tree protection or variance the city requires. Finishes matter too: a rental-grade kitchenette with laminate counters costs far less than a full-size kitchen with custom cabinetry. The way to avoid overpaying is to get a written price that includes site work, permits, plans, and finishes in one number, so you’re not approving a foundation bid and then discovering the electrical isn’t included. Our free estimate walks your lot and puts the real number in front of you before you commit to anything.
Our Service Area Near Austin
Fielding ADU Austin builds ADUs across the Austin metro. We serve homeowners in Georgetown, Pflugerville, San Marcos, Lakeway, Hutto, Buda, Manor, Brushy Creek, Lago Vista, Wells Branch, and Hornsby Bend. If you’re outside the city limits but still in Travis or Williamson County, call us anyway. You can also read more about our work in ADU Builders in Georgetown and ADU Builders in Pflugerville. Our home page has details on the full Garrison Partners family of services.
Serving Austin, TX - Our Local Coverage Area
We’re based in the Austin area and, like Buda ADU Builders, know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About ADU Builders in Austin
An ADU builder is a contractor who specifically builds accessory dwelling units: detached backyard homes, garage conversions, and JADUs. The difference between a general contractor and an ADU builder is that the ADU builder knows Austin’s specific ADU code, setback rules, and permit process and has built enough units locally to price them accurately. Fielding ADU Austin exists specifically to build ADUs and room additions.
A garage conversion or JADU typically takes 3 to 5 months from permit submission to final inspection. A detached backyard ADU takes 6 to 10 months depending on site work and whether you choose a prefab platform like Abodu or a conventional build. Permit review time in Austin is the biggest variable, and a complete plan set shortens it. Call (361) 309-9568 and we’ll give you a realistic timeline for your specific lot.
A garage conversion runs $90,000 to $150,000, a JADU runs $70,000 to $130,000, and a detached backyard ADU runs $180,000 to $390,000. These are complete-project numbers including plans, permits, site work, construction, and finishes. Your exact number depends on your lot, your soil, your panel, and your finish choices. Call (361) 309-9568 for a free site evaluation and written price.
Yes. We install Abodu and Cover prefab units and we convert Tuff Shed-style structures into habitable space under Austin code. Each platform has specific foundation, utility, and finishing requirements, and we handle those for you. If you already own a unit or are thinking about buying one, call us before you pay for it so we can check your lot for fit.
If an ADU under our one-year guarantee fails, we return and fix it at no charge. If you have a water leak, a failed electrical circuit, or a structural concern in any ADU, call (361) 309-9568 and a live person will answer at any hour. We’ll schedule the right crew for the problem.
Every project gets The Garrison Standard: a written one-year guarantee covering workmanship defects. If something fails inside that year, we come back and correct it at no charge. The guarantee is spelled out on paper when you sign, including what it covers and exactly how we make it right.
Walk your lot and know where the water, sewer, and electrical lines run. Check your electrical panel’s amperage rating if you can. Know whether you want a rental unit or a family space, because that changes the design. Then call (361) 309-9568 and we’ll do the rest, starting with a free site walk.
Schedule Your ADU Builders Service in Austin Today
If you’re ready to get a written price for your Austin ADU, call (361) 309-9568. We’ll walk your lot, check the setbacks, and tell you what can be built and what it will cost. No obligation, no pressure, and a real person answers the phone any time you call. The estimate is free.
Written by Reed Calloway, Owner at Fielding ADU Austin, serving Austin since 2006.
