Garage Conversion ADU in Round Rock - Plans, Permits & Build, One Fixed Price

Fast, Reliable Garage Conversion ADU Across Round Rock

Garage conversion ADUs in Round Rock typically run $140,000 to $260,000 all-in, drawings through final inspection, with attached conversions landing on the lower end and detached builds with new foundations on the higher end. The number on your project depends first on one question most general contractors never ask: what does your HOA actually allow? We serve Round Rock from our Austin scheduling office with crews working locally, and we’ll tell you the HOA truth before you spend a dollar on drawings. Call (971) 497-2402 to start with a written scope and price, not a vague estimate.

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Why Ellery ADU Studio Is Round Rock’s Preferred Garage Conversion ADU Company

Round Rock isn’t Austin, and that distinction matters more here than anywhere else in Williamson County. Homeowners call us after reading about Austin’s 2019 ADU deregulation, assuming those reforms apply to Round Rock. They don’t. Round Rock is a separate municipality with its own code, and a large share of its housing stock sits in HOA-governed master-planned communities like Teravista, Stone Canyon, and the Brushy Creek corridor. We know which subdivisions have CC&Rs that prohibit independent kitchen facilities in accessory structures, and we’ll tell you before you’re committed to anything. We’re a Garage Conversion ADU design-build studio, not a contractor, which means the permit set, the drawings, and the construction are one contract at one written price. No designer blame-shifting to the builder. Since 2015, Ellery ADU Studio has designed, permitted, and built more than 900 ADUs, every one with a written price before work started. Nadia Ellery leads the studio, and our work is governed by The Haven Standard: a written price before any work begins (Clause 1), a documented photo record on every visit, and a 365-Day Done Right Promise that says, in writing, if the finished ADU isn’t built to the permitted drawings, we make it right. That’s the difference between a contractor who wins the job and a studio that stands behind the permit set.

Our Garage Conversion ADU Services in Round Rock

The right conversion approach depends on your garage’s placement, your lot’s setback lines, and what your subdivision’s deed restrictions allow. We scope four distinct paths in Round Rock:

Attached Garage Conversion

Most Round Rock tract homes built between 1985 and 2015 have an attached two-car garage sharing a wall with the main house. Converting it means working within the existing footprint, which usually keeps you clear of setback variances (the extra distance the city requires between a new structure and your property line). We’ve converted attached garages in Brushy Creek and Teravista, and the HOA architectural review board is almost always the first approval you need, not the city permit office. Expect $140,000 to $190,000 for a one-bedroom conversion with a full bath and kitchenette, depending on whether your HOA requires architectural changes to the street-facing elevation.

Detached Garage Conversion

A detached garage gives you more privacy and separation, but on Round Rock’s expansive black clay soil, it also means foundation scrutiny. Most existing detached garage slabs in 1990s-era subdivisions were poured as standard residential slabs, not engineered for living space. We’ll assess whether your slab can handle the load or whether you need a new pier-and-beam or engineered foundation. Detached conversions in Round Rock run $180,000 to $260,000, with foundation work often representing $18,000 to $35,000 of that. The heat gain on a west-facing garage door wall is another line item that surprises people, and we’ll talk through that before drawings begin.

Carport Conversion

Carports are rarer in Round Rock than in older Texas cities, but you’ll find them on pre-1970s lots near historic downtown Round Rock and along aging corridors near Mays Street. Converting a carport to an ADU almost always means building new walls, a roof, and a foundation, which puts this project in the $160,000 to $220,000 range. The older lots near downtown also tend to be smaller, so we’ll calculate your lot coverage ratio against Round Rock’s zoning before you commit to a footprint.

Garage JADU

A Junior ADU, or JADU, converts part of your garage or an attached room into a smaller living unit with its own entrance, but it can share a bath or kitchen connection with the main house. For Round Rock homeowners who want rental income or a space for a parent without the cost of a full ADU, a garage JADU runs $80,000 to $130,000. The lower cost comes from the shared utility infrastructure, which means less trenching, fewer new lines, and a simpler permit path. In Teravista and other master-planned subdivisions, a JADU sometimes faces fewer HOA objections than a full ADU because it doesn’t always trigger the same “independent kitchen facility” language in the CC&Rs. We’ll read your deed restrictions before you pay for anything.

Garage Partition & Bathroom Add

If you want a guest suite or home office inside your garage footprint but don’t need a full kitchen, a partition and bathroom addition is the leanest option: $60,000 to $110,000 depending on plumbing distance from the main line and whether your garage slab needs cutting. This path works well for Round Rock homeowners who want a quiet office separate from the main house but don’t want to trigger the full HOA review process that a kitchen-equipped ADU requires. We’ll frame the partition, add the bath, insulate to code, and document every step with photos.

Trusted Brands We Service in Round Rock

If you’re leaning toward a prefab or modular ADU on your Round Rock lot, we specify and coordinate systems from Cover, Dvele, and Boxabl within the same single contract. We don’t hand you a brand catalog and disappear. We handle the site prep, the permitting, the foundation, and the utility hookups, then coordinate the module delivery and finish work. The benefit is a factory-built shell with on-site control over the foundation and connections. For Round Rock’s clay soil, that foundation control matters more than the module itself. You get a written price for the whole package before anything is ordered.

Common Garage Conversion ADU Problems We See in Round Rock Homes

• HOA deed restrictions kill projects before permits exist. In Teravista, Stone Canyon, and Walsh Ranch-adjacent communities, the CC&Rs often prohibit accessory structures above a certain square footage or any structure with an independent kitchen. No city permit overrides a deed restriction. We read your HOA documents first and tell you whether a full ADU, a JADU, or a different path is realistic.
• Builders and homeowners assume Austin’s ADU reforms apply here. Round Rock is under Williamson County with its own zoning code. Austin’s 2019 deregulation changes nothing for you. If a contractor tells you Round Rock follows Austin’s ADU rules, the contractor hasn’t read the Williamson County code.
• Expansive black clay soil cracks standard slabs. Central Texas’s notorious clay heaves and shrinks with wet-dry cycles. A standard residential slab under an ADU extension will move, and within a year you’ll see drywall cracks and door misalignment. We specify engineered slabs or pier-and-beam foundations for detached ADUs in Round Rock, full stop.
• Undersized HVAC is the top post-occupancy complaint. West-facing garage door walls in Round Rock’s summer heat turn a converted space into an oven if the mechanical system is sized for the original garage, not the finished living area. We calculate heat gain on the actual orientation of your garage and right-size the mini-split or ducted system before you sign.

Pricing for Garage Conversion ADU in Round Rock, TX

We Also Serve Cities Near Round Rock

Beyond Round Rock, our crews serve Pflugerville, Cedar Park, Leander, and Austin. If you’re in a Williamson County subdivision or an Austin neighborhood considering a Garage Conversion ADU in Round Rock, the same HOA-first and clay-soil-first approach applies. Call us and we’ll tell you what your specific deed restrictions and soil conditions mean for your project.

FAQs - Garage Conversion ADU in Round Rock