







Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Delta Home Additions & ADU: The San Antonio Owner’s Guide
Home additions and ADU construction in San Antonio typically run $45,000 – $130,000 for an addition and $90,000 – $220,000 for a detached ADU, with most projects taking 4 – 10 months depending on scope, permitting, and foundation work. We’re Elmstead Remodeling San Antonio, a Cedarwell company, and we handle full home additions and ADU construction with a written price before any work starts. Homeowners usually reach out to us at one of two moments: they’ve outgrown the house but love the street, or they’ve inherited a property in San Antonio where an ADU could offset the mortgage and the family needs the income.
What pulls a Delta-family addition or ADU project off schedule in our experience is rarely the big framing moment. It’s the smaller decisions that surface after demo: the plumbing rough-in that wasn’t in the first quote, the soil report that changes the foundation plan, the window package that goes on backorder. That’s why we write the scope down in detail before the first tool leaves the truck, and why the price you sign is the price you pay. Graham Stein grew up in Los Angeles and learned the trade at LA Trade-Tech before framing and finishing homes across San Antonio, and he still insists on the same discipline: write it down, price it once, do it right.
Key Takeaways
- Typical home addition in San Antonio: $45,000 – $130,000; detached ADU: $90,000 – $220,000
- We provide a written line-item price before any work starts, governed by the Cedarwell Care Promise
- Named-brand materials throughout: KraftMaid and Wellborn cabinets, Cambria and Silestone countertops, Kohler, Moen, and Grohe fixtures, James Hardie exteriors
- 365-Day Done Right Promise on every completed project: if it’s not done right, we make it right
- Call (432) 233-0976 to schedule a free estimate
Styles & brands we work with







Which Delta Models This Applies To
Delta doesn’t make home additions or ADUs, of course. If you’re planning an addition or ADU in San Antonio, at some point you’ll need fixtures, faucets, trim, and hardware that carry the Delta name. The get-to-it point is compatibility between the Delta fixtures you already have in the main house and the ones going into the new space. Delta’s current lineup splits across a few families: Classic (value-focused, common in rental ADUs), Broderick and Cassidy (mid-range, works well for bathroom additions), and Trinsic, Vero, and Leland (the higher-end lines with pull-down kitchen faucets and touch options).
If you have a Delta kitchen faucet and want the same touch in the new addition, check the base of the spout or the underside of the handle for the model number printed on a small sticker. Delta’s parts database matches by that model number, and most valves across the MultiChoice shower system accept different trims. Meaning you can put a basic Delta shower valve in an ADU and swap the trim later without opening the wall. One compatibility gotcha we see regularly in San Antonio: older Delta faucets from the 1990s and early 2000s use a different cartridge thread than current models, so the new sprayer head won’t thread onto the old hose. We flag that before ordering anything rather than after the finish plumbing is in.
We’re an independent contractor, not affiliated with Delta. What we bring is parts-matching know-how and the willingness to stand behind the finished work. For the broader project, we install cabinets from KraftMaid, countertops from Cambria and Silestone, and solid brass fixtures from Delta’s Trinsic and Leland lines when a family wants the same finish language carried through the whole house.
Signs Your Delta Home Additions & ADU Is Failing
This isn’t a part that fails quietly, and it isn’t one part. It’s the accumulated small failures in the existing house that tell you the addition or ADU is overdue:
- The hallway bathroom faucet drips even after the handle is fully closed. In San Antonio’s hard water, the cartridge seats inside Delta valves wear faster than the same part would in soft-water markets. That drip is a $15 cartridge today and a subfloor repair later if it’s left running against the basin’s overflow path.
- You’ve stopped inviting people over because the living room only seats four. For families with kids and pets, the first sign an addition is needed is usually a weekly resentment, not a building inspection. A 400-square-foot family-room addition is the most-requested scope we frame.
- The ADU’s door binds in the frame when the San Antonio clay soil moves after a wet spring. Movement like that points to foundation work or at least a leveling correction before any finish drywall goes up. We address it before the trim carpenters arrive, not after.
- Every bedroom in the house is spoken for, and the pets have better sleep arrangements than the guests. That’s an ADU or a bump-out addition decision, and it usually means permit drawings and a soil report first in San Antonio’s engineering district boundaries.
- The Delta fixtures in the existing house are a mix of three finishes and two eras. When we build the addition, we carry one finish family through the whole project, and that means swapping cartridges and trims in the old bathrooms at the same time so the house reads as one home instead of a before-and-after.
See the difference
Before
After
Before
After
Before
AfterReplacement Cost & What’s Included
For a home addition in San Antonio, a written price falls between $45,000 and $130,000 depending on square footage, whether it’s a one-story bump-out or a two-story vertical addition, and what the city’s development services department requires for the parcel. An ADU runs $90,000 to $220,000, driven by site work, utility connections, and whether you choose a slab-on-grade or pier-and-beam foundation.
What’s included in our written price: drawings and permits pulled by us, foundation and framing, roofing or tie-in to existing structure, electrical and plumbing rough-in and finish, drywall and painting, flooring, named-brand cabinets and countertops, Delta fixtures where the family wants them, and finish trim. What’s also included, every time, with no invoice line item for it: shoe covers and drop cloths inside the main house while the work runs, quiet tools during children’s rest hours where possible, a photo of the clean-up before the crew leaves, and the 365-Day Done Right Promise. If something isn’t done right, we come back and fix it.
DIY or Call Us?

If the Delta fixture in the existing house has a leaking cartridge, that’s a homeowner-level repair if you know the model number and have the right tool. Changing a MultiChoice trim kit is straightforward. Swapping a shower cartridge is done in under an hour by most handy owners, and Delta’s parts diagrams are clear.
But a home addition or ADU is not a weekend project, and San Antonio’s local rules are real: engineering for clay soil, tree-protection zones, impervious-cover limits, and utility easements all affect what can be built and where. The expensive mistake is not the construction; it’s building something the city won’t sign off on. We pull the permits, we schedule the inspections, and we fix whatever the inspector flags. If you’re at the point where the family needs the space, call (432) 233-0976 and we’ll walk the property together before you spend a dollar on drawings.
FAQs
Most additions take 4 – 7 months and most ADUs take 6 – 10 months from permit application to final inspection in San Antonio. The city’s permitting review window and the availability of foundation crews are the two most common schedule variables.
Often yes. A bump-out addition of 200 – 400 square feet is frequently less disruptive than a full ADU for families in established neighborhoods like King William or Alamo Heights where lot coverage rules are tight. We’ll tell you honestly which path makes sense for your parcel before any drawings are produced.
No. The written price we give you before work begins is the price you pay. The only time a number changes is if you ask us to add scope in writing, and that gets signed as a separate line item before the work, never after.
We install Delta fixtures when a family wants them, especially the Trinsic and Leland lines, and we match cartridges and trims across the old and new parts of the house so there’s one finish family throughout. We also install Kohler, Moen, and Grohe fixtures where a family prefers those.
Written by Graham Stein, Owner, Elmstead Remodeling San Antonio at Elmstead Remodeling San Antonio, serving San Antonio and nearby areas.


