Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
IKO Home Additions & ADU: The San Antonio Owner's Guide
When you're planning an IKO home addition or ADU in San Antonio, the single most important decision happens before a single board is cut: getting a written scope of work and a fixed price you can hold in your hand. Home additions in San Antonio typically run $45,000 to $130,000, while a full ADU construction project lands between $90,000 and $220,000. Most families call us because they have a growing household, aging parents moving in, or a rental unit they want to build in the backyard. The work is big, the budget is real, and the contractor you choose determines whether the process feels orderly or like a year of surprises.
We walk every San Antonio home addition the same way: room by room, naming the materials, the framing details, and the schedule before anything gets signed. In neighborhoods like Alamo Heights, Terrell Hills, and the King William Historic District, we have seen how roof lines, setback requirements, and foundation conditions shift the price. That is why the written price comes first, always.
Which IKO Models This Applies To
IKO manufactures a range of roofing and building products, and when an addition or ADU is framed and roofed, the IKO materials on the existing house need to tie into the new structure correctly. The key is matching the shingle line, underlayment, and flashing details to what is already on the roof. IKO's architectural shingle lines, including the Cambridge and Dynasty series, are common on San Antonio homes, and matching the exact color and profile matters more than most homeowners expect. A mismatched shingle is visible from the street, and in a historic district like King William, it can also run into design review issues.
If you are adding a second story or extending the roofline, we verify the existing IKO shingle series by checking the original packaging, the bundle label, or in some cases the roof's installation paperwork. OEM IKO shingles are our default recommendation for any visible roof slope, because the color match and wind warranty stay consistent. For underlayment and ridge cap that sit beneath the surface, a quality aftermarket equivalent that meets IKO's minimum specs can work, but we document that choice in the written scope so there is no confusion later. Elmstead Remodeling San Antonio is an independent contractor and not affiliated with IKO. What we bring is field experience matching IKO materials on Texas roofs, where heat and hail shorten the life of a roof a lot faster than the manufacturer's warranty suggests.
Styles & brands we work with
Signs Your IKO Home Additions & ADU Is Failing
- Water staining on the ceiling where the addition meets the original house. This is usually a flashing failure at the roofline transition, not the shingles themselves. San Antonio's heavy spring storms push water sideways, and a small gap in the step flashing turns into a slow leak that soaks the insulation before you ever see a stain.
- Roof shingles lifting or curling along the new roofline. If the addition's roof pitch doesn't match the original, or if the sheathing wasn't properly vented, heat builds up. IKO shingles on a poorly vented roof age faster than they should, and in San Antonio summers that means a 25-year shingle can look worn at year 12.
- Gaps opening at the addition's foundation line. San Antonio's clay-heavy soil expands and contracts with moisture, and new construction settles. Hairline cracks are normal in the first year. Gaps wider than a quarter inch, or doors inside the addition that start sticking, mean the foundation was not engineered for the soil movement.
- Doors and windows in the new space losing their seal or sticking. This can be settling, but it can also be framing lumber that was too wet when installed. As it dries in the Texas heat, studs twist, and openings shift just enough to annoy you every single day.
- The addition never quite matches the original house, no matter how it was flashed. Sometimes the problem isn't a failure at all; it is that the original plan didn't account for how the two roof lines and eave heights would look together. That is a design miss, and it is preventable when the scope of work is written down and the elevations are checked before framing starts.
See the difference
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After
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AfterReplacement Cost & What's Included
In San Antonio, a home addition runs $45,000 to $130,000, and an ADU construction project runs $90,000 to $220,000. The spread comes from square footage, foundation type, roof complexity, and whether the project needs a new HVAC zone or a panel upgrade. A garage conversion sits in a different band, $30,000 to $80,000, because the shell already exists.
What matters more than the number itself is what is inside it. Our written price for any San Antonio home addition includes the framing, roofing, siding, drywall, paint, and trim for the new space, plus the permits pulled and the inspections passed. It includes the drop cloths on the existing floors, the shoe covers at the door, and the photo of the clean-up before we leave each day. If the price changes, you will hear it before the work changes, not after. And every project carries the 365-Day Done Right Promise: if something is not done right after the job is complete, we make it right.
DIY or Call Us?
A home addition or ADU is not a DIY project, and we say that plainly because the dangerous parts are not obvious from the outside. Roofing work at height, electrical runs into a new subpanel, and gas line extensions for a new range all carry real injury risk. The framing and roofline tie-in, where the new IKO materials meet the existing structure, is where leaks begin and are hardest to fix later.
What an owner can do is useful groundwork: walk the property line and check your setback requirements with the city of San Antonio, gather your IKO shingle information if you know it, and write down the rooms, sizes, and functions you want. When you call (432) 233-0976, we will send someone to walk the space with you. The estimate is free, and the price you get is the price you pay.
FAQs
A properly built San Antonio home addition should last as long as the original house, with the roof as the first major replacement point. IKO architectural shingles in our climate typically deliver 15 to 20 years of reliable service before heat and hail wear them down. The framing and foundation, if engineered for San Antonio's clay soil, are built to last the life of the home. Call (432) 233-0976 and we will walk you through what to expect for your specific project.
Most addition problems, like flashing leaks, door sticking, or venting issues, can be repaired without tearing the addition down. Foundation movement is the one that sometimes requires major work. The key is identifying the actual cause before opening walls. We write the scope down and price the repair once, so you know what you are getting before the first tool leaves the truck.
A typical San Antonio home addition takes three to six months from permit to final walkthrough, and an ADU runs four to nine months depending on utility connections and foundation work. The city of San Antonio permitting process adds time that good planning can shorten. We give you a written schedule with the written price, and we protect your family's routine through the whole build: quiet tools during rest hours, drop cloths inside, and a clean-up photo before the crew leaves.
We source IKO materials through our local San Antonio suppliers and bring them to the job, which means you are not running to a lumberyard on a Saturday. Our partners also include KraftMaid and Cambria for cabinetry and countertops, and Silestone where the design calls for it. We verify the IKO shingle match before we order, and we check the material on delivery, so the roof on your new addition looks like it was always there.
Written by Graham Stein, Owner, Elmstead Remodeling San Antonio at Elmstead Remodeling San Antonio, serving San Antonio and nearby areas.
