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Atlas Home Additions & ADU: The San Antonio Owner’s Guide
If you’re searching for Atlas home additions and ADU parts in San Antonio, the honest answer is this: Mason Remodeling Co San Antonio installs and services Atlas-compatible addition and ADU components, and a full home addition or ADU build in the San Antonio market typically runs $45,000 to $220,000 depending on scope, square footage, and site conditions. What fails on an Atlas project isn’t usually one dramatic part; it’s the slow stuff: a roofline flashing detail that gave up after a hailstorm, a subfloor seam that’s been flexing for years, or original builder-grade windows letting conditioned air escape into a Texas August. Most owners call us after noticing a draft where there shouldn’t be one, a door that suddenly won’t latch, or a water stain creeping across a ceiling that was bone-dry last spring.
We’re an independent San Antonio contractor, not an Atlas factory rep. That means we diagnose the actual failure, source the correct component, and install it without a sales pitch attached to the part number. You should also know we stock common Atlas-era framing connectors, flashing profiles, and door hardware on our trucks for the additions we service across the city.
Key Takeaways
- Installed Atlas addition and ADU repair pricing in San Antonio ranges from $45,000 for smaller additions to $220,000 for full ADU builds.
- We stock common Atlas components on our trucks for faster turnarounds on service calls.
- Mason Remodeling Co San Antonio is an independent contractor, not affiliated with Atlas, and we put a written price in your hands before any work starts.
- Isaac Pruett and his crew have worked San Antonio additions for years, from King William Historic District gut renovations to quiet neighborhood kitchen rebuilds.
Which Atlas Models This Applies To
Atlas home additions and ADU projects vary more by era than by model number, and that’s the first thing you need to know when ordering parts. Pre-2015 Atlas additions in San Antonio typically used standard dimensional lumber framing with 16-inch on-center spacing and basic engineered trusses. Newer builds lean toward wider 24-inch spacing with I-joists and higher-performance sheathing. The window rough openings changed too, especially after Texas adopted stricter energy codes, meaning a window ordered for a 2009 Atlas addition won’t always drop cleanly into a 2021 opening without shimming and flashing rework.
Here’s where it gets specific: if you have an Atlas ADU with a low-slope roof, the edge metal profile is likely a custom-formed drip edge that doesn’t match anything at the big-box lumber yard. We measure, form to match, and install the correct gauge. For OEM parts, Atlas generally used industry-standard brands: Simpson Strong-Tie connectors, LP or Huber sheathing, and Marvin or Milgard windows depending on the build year. Quality aftermarket equivalents from Simpson or MiTek are perfectly fine for structural connectors. For windows, match the original glass package and frame depth, or you’ll fight the trim detail and the U-factor rating. Send us a photo of the label on the failed part or the corner of the window sash, and we’ll tell you exactly what you’re looking at.
Styles & brands we work with
Signs Your Atlas Home Additions & ADU Is Failing
- Drafts around window and door perimeters. The original flashing tape on older Atlas additions dries out and delaminates after 10 to 15 San Antonio summers. Air moves through the gaps, and you’ll feel it before you see it.
- Water staining at the ceiling-to-wall junction. On low-slope ADU roofs particularly, the membrane at the parapet wall is the first failure point. A dark yellow-brown stain creeping along that line means water is getting past the edge detail.
- Doors that won’t latch in summer. San Antonio’s clay-heavy soils swell and shift with moisture. An addition built on a slab without proper soil preparation will move enough to throw door frames out of square. The frame itself may be fine; the foundation beneath it is doing the talking.
- Cracking drywall at the seam where the addition meets the original house. The structural tie-in between old and new framing always moves a little. If the crack is hairline and stable, it’s cosmetic. If it widens seasonally, the connection detail needs to be examined.
- Soft spots on the subfloor near exterior doors. We see this regularly in Atlas additions where the door threshold flashing was installed over, not under, the sheathing edge. Water wicks in, and the OSB rots from below. What looks like a small soft spot is usually a larger repair once we open it up.
See the difference
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AfterReplacement Cost & What’s Included
Full home addition work in San Antonio runs $45,000 to $130,000. ADU construction runs $90,000 to $220,000. Garage conversions fall between these at $30,000 to $80,000. The spread comes down to three things: whether the addition ties into existing rooflines or gets its own ridge, whether you’re reusing existing HVAC capacity or adding a mini-split or new trunk line, and whether the site prep requires piers or additional slab work. A flat-lot room addition with simple gable roof and existing HVAC capacity lands at the low end. A full ADU with kitchen, bath, separate meter, and new sewer lateral lands at the top.
Every price we quote in San Antonio is written before any tool is unpacked. That’s the Mason Remodeling standard and it’s been that way since 2004. You’ll see the line items: rough framing, roofing, windows, drywall, electrical, flooring, paint, trim. No verbal ballparks that mysteriously grow at invoice time. The work carries our 365-Day Done Right Promise: if it’s not right within a year of completion, we make it right at no cost to you. You’ll also get a written guarantee with coverage terms spelled out, including what’s excluded and for how long.
DIY or Call Us?
For a window that won’t latch or a door that drags, there are checks you can safely do yourself: look at the gaps around the frame, check whether the threshold is pitched toward the outside, and verify the weatherstripping is still soft and seated. You can reseal a gaps with quality exterior caulk. What you shouldn’t do is open a wall cavity that shows signs of water damage or attempt roof edge repairs on a low-slope ADU. The second you’re on a ladder at the roofline, the risks include not just the fall, but the high-tension work of cutting back damaged membrane while balanced on the same surface that’s already failing.
If you’re in San Antonio and the problem is structural, water-related, or involves anything on the roof, call us at (254) 269-5071. We’ll send out Isaac Pruett or one of our leads to look at the actual condition, and you’ll get a written price for the repair before you commit to anything. Free estimates, no pressure.
FAQs
How long do Atlas home addition and ADU components last in San Antonio? Roofing and flashing details on additions and ADUs in this climate typically last 12 to 20 years depending on sun exposure and storm cycles, while window units and door hardware generally run 15 to 25 years before they need real attention. The Texas heat and occasional hailstorm age exterior components faster than a mild coastal climate, so we lean toward the shorter end of those ranges when we set expectations.
Can a failing Atlas addition component be repaired instead of replaced? Yes, in many cases. Cracked flashing can often be resealed and re-fastened, doors can be re-hung and adjusted, and window sashes can be rebuilt. Repairs stop making financial sense when the surrounding framing or sheathing shows rot, or when the component is at the end of its service life anyway. We’ll show you both options with written pricing and let you decide. Call (254) 269-5071 for an on-site assessment and a written quote.
How long does it take to fix a failing Atlas addition or ADU in San Antonio? Most component-level repairs like door replacement, window re-flashing, or a subfloor section fix take one to three days on-site. Full addition or ADU rebuids run eight to sixteen weeks depending on scope, permitting, and weather. We give you a written schedule with the estimate so there’s no guessing.
Do you stock Atlas addition and ADU parts on your trucks in San Antonio? Our trucks carry the common framing connectors, flashing profiles, threshold details, and door hardware we’ve learned to expect from Atlas-era projects across San Antonio. For specialty items like custom window sizes or matched trim profiles, we order from the same suppliers the original builders used. If we’re not certain we can source an exact match quickly, we tell you before you spend a dollar.
Written by Isaac Pruett, Owner, Mason Remodeling Co San Antonio at Mason Remodeling Co San Antonio, serving San Antonio and nearby areas.
