A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable ADU Builders Across Boerne
Adding an ADU in Boerne means navigating three layers of rules at once: city code, HOA design standards, and, for older properties near Main Street, the Historic Landmark Commission. We’ve handled all three. Our crews build detached ADUs, JADUs, garage conversions, and prefab installations across Boerne’s neighborhoods, from the limestone cottages near Cibolo Creek to the new master-planned communities off I-10 and River Road. Ben Ortega leads every Boerne project personally, and you can reach our live scheduling team around the clock at (210) 981-6358. No phone trees, no waiting until Monday.
Why Seedling ADU San Antonio Is Boerne’s Preferred ADU Builders Company
Boerne homeowners deal with a specific set of questions most builders never discuss openly. Will the Historic Landmark Commission reject your JADU roofline? Will your builder’s 10-year structural warranty survive an attached addition? Do you need a French drain because your lot sits on former ranchland that still floods in spring storms? We answer those before we ever quote a price. That’s why families in Esperanza, Front Gate, and the older streets off River Road keep referring us to neighbors. Our ADU Builders team shows up in uniform, background-checked, with shoe covers on before anyone crosses your threshold.
Every Boerne project gets a written price before work begins. Every single one. And after the final inspection, the 365-Day Done Right Promise still applies. If something wasn’t done right, we make it right. That’s not marketing language; it’s the same promise we make in writing on each contract.
JADU in Boerne
A JADU in Boerne – a Junior Accessory Dwelling Unit built within the footprint of your existing home – typically runs $75,000 to $140,000 depending on whether you’re converting an attached garage, finishing a basement, or carving space from an oversized utility room. Boerne homeowners choose JADUs when they want rental income or a private suite for aging parents without the longer permitting path that comes with a detached structure.
Attached Garage Conversions
On newer Boerne homes, an attached garage conversion usually costs $65,000 to $95,000 for a 400 sq ft JADU with a kitchenette and bath. On older homes near downtown, expect to add $8,000 to $15,000 for electrical panel upgrades and sewer line replacement. The Historic Landmark Commission cares about window placement on street-facing walls, so we handle that design review as part of the quote.
Builders Warranty Protection
If your home is still under the original builder’s 10-year structural warranty, we notify the builder before cutting into any load-bearing or exterior wall. That written notification preserves your warranty coverage. Skipping that step voids it, and we’ve seen it happen to smart, careful homeowners who just didn’t know the process. We do, and we include it in our scope of work at no added cost.
ADU Plans in Boerne
ADU Plans in Boerne – the full architectural and permit drawing set your project needs before any dirt moves – typically cost $6,000 to $18,000, depending on whether you’re working with a prefab shell that ships with engineering stamps or a fully custom design. In Boerne’s master-planned communities, those plans also have to pass an HOA architectural committee review, which is a separate approval from the city’s building department.
Prefab and Modular Shell Plans
When you choose a Dvele, Boxabl, or Plant Prefab shell, the manufacturer’s engineering already covers structural drawings. Our job is the site plan, foundation design, utility connections, and the finish schedule your HOA will require. We’ve handled Plan Prefab and Dvele submittals for Boerne HOAs, including Esperanza’s HOA, which required a specific James Hardie Artisan siding color called Aged Pewter on the project we completed off River Road.
Custom Design and Historic Review
A fully custom ADU plan for a property in the Historic Landmark Commission zone runs $14,000 to $20,000 because the commission reviews elevation drawings, window styles, and roofline compatibility. We’ve matched 19th-century German stonework before, and we keep photos of approved projects to show the commission what’s worked. In Boerne, that specific history makes an ADU plan different from one for a San Antonio subdivision, where plan review usually stops at the building department.
Trusted Brands We Service in Boerne
We work directly with Boxabl and Plant Prefab for prefab shells, and we stock James Hardie siding materials in the finishes Boerne HOAs request most. When an HOA requires a specific Hardie color or a standing-seam metal roof, we don’t have to order those from a distant distributor and wait. We keep the common Boerne specs ready, which means fewer days between framing and paint. Tuff Shed shells also work for some Boerne homeowners, though master-planned communities have stricter rules we’ll walk you through before you buy anything.
Common ADU Builders Problems We See in Boerne Homes
- Voided builder warranties. A homeowner cuts into the main home for an attached JADU without notifying the original builder. The builder later denies a structural claim because the notification never happened. We handle the notification step in writing before work starts.
- HOA architectural violations. Standard asphalt shingles go on an ADU in a community whose architectural committee requires metal roofing. The HOA issues a cease-and-desist. We pull the HOA finish schedule during estimating so your quote matches the rules from day one.
- Foundation washout on former ranchland. Boerne’s spring storms dump enough rain to overwhelm grading that’s been unchanged since the land was ranch property. We raise foundations above grade and install French drains, especially near Cibolo Creek.
- Cooling failures in 100-degree summers. An ADU without its own high-efficiency mini-split becomes unusable in Boerne’s July and August heat. We spec HVAC for the ADU’s actual square footage and insulation, not just the cheapest window unit that fits.
Pricing for ADU Builders in Boerne, TX
A detached custom ADU in Boerne runs $180,000 to $320,000 for a 600 to 900 sq ft unit. A prefab ADU using Boxabl or Plant Prefab shell lands between $130,000 and $220,000, including site work, foundation, utility connections, and interior finishes. JADUs inside your existing home cost $75,000 to $140,000. Garage conversions run $95,000 to $150,000 depending on plumbing proximity and electrical panel capacity. What moves the number: HOA finish requirements, foundation height, drainage work, and historic district review. You’ll get a written line-item price before any work starts. Call (210) 981-6358 to schedule your free estimate.
We Also Serve Cities Near Boerne
Our Boerne crews also handle ADU projects in Helotes, San Antonio, Universal City, and Cibolo. If you’re in one of those cities and weighing an ADU or garage conversion, the same written pricing and 365-Day Done Right Promise apply. Call us and we’ll tell you what your local city and HOA will actually require.
Serving Boerne, TX - Our Local Coverage Area
We’re based in the Boerne 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 About ADU Builders in Boerne
Yes. The commission reviews ADU exteriors for compatibility with your home’s original materials and roofline, and on properties with 19th-century German stonework, they will require stone matching, specific window patterns, and rooflines that don’t compete with the main house. We’ve navigated these reviews and keep photo documentation of approved Boerne projects to support new applications. Call (210) 981-6358 and we’ll tell you what your specific property will need.
Notify the original builder in writing before any wall penetration or structural change, keep a copy for your records, and follow the builder’s process for a detached ADU rather than an attached JADU if the warranty explicitly excludes additions that connect to the main structure. We handle builder notification as a standard part of any project on a home still under warranty. Call (210) 981-6358 for a free review of your warranty language.
Many Boerne master-planned communities, including Esperanza, collect a separate architectural review deposit when you submit ADU plans. The amount varies by community and is typically refundable if the committee approves the project and you complete construction per the approved finish schedule. We identify these deposits during estimating so they appear in your written price. Call (210) 981-6358 and we’ll confirm what your HOA requires.
Usually not as a primary dwelling. Boerne’s master-planned communities enforce minimum finish standards that Tuff Shed shells alone won’t meet, especially on siding, roofing, and window specifications. A Tuff Shed can work as a studio workshop or storage unit, but a livable ADU will need upgraded cladding and insulation. Call (210) 981-6358 before you buy a shed shell; we’ll tell you exactly what your HOA will approve.
If your lot sits within a FEMA floodplain along Cibolo Creek, your lender will require flood insurance on the ADU, and Boerne’s building department will require flood-resistant foundation construction. We raise foundations above base flood elevation and add drainage to keep your ADU dry through spring storm season. Call (210) 981-6358 and we’ll check your lot’s flood zone before you spend money on plans.
Written by Ben Ortega, Owner at Seedling ADU San Antonio, serving Boerne’s ADU needs with written pricing and the 365-Day Done Right Promise.
