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ECO Window Systems Home Additions & ADU: The San Antonio Owner’s Guide
A home addition or ADU built around ECO Window Systems windows and doors in San Antonio typically runs $45,000 – $130,000 installed, depending on square footage, foundation work, and finish level. We stock and install ECO Window Systems-compatible framing, flashing, and glazing components, and we can usually get a failed window or door assembly back in service within a few days once we confirm the model and measurements. Most San Antonio homeowners realize something’s wrong when they get a water stain on fresh drywall, a window that won’t latch square, or a door slab that drags after a big temperature swing. These aren’t cosmetic annoyances in a custom build. They’re symptoms of a component that was either installed slightly off-plane or has shifted with our clay soil.
Key Takeaways
- Replacement parts for ECO Window Systems windows, doors, and seals in an addition or ADU run from a few hundred dollars for hardware to several thousand for a full multi-panel glazing swap.
- We identify your exact ECO Window Systems model before ordering anything, because mixing series can ruin sightlines and void your wall assembly.
- Texas heat and UV are the leading killers of glazing seals and weatherstripping on these units, not age alone.
- Written price before work starts, photo updates, live arrival tracking from us. Same standard on a $600 part replacement as a $130,000 addition.
Which ECO Window Systems Models This Applies To
ECO Window Systems produces several window and door lines, and the hardware, glazing beads, and weatherstripping are not fully interchangeable between them. The two we run into most often on San Antonio additions and ADUs are the ECO 200 series (fixed and single-hung, narrower frames, common in ADU accessory units) and the ECO 300/400 series (wider extrusion profiles, better thermal breaks, more often in primary-room additions). There’s also the ECO patio door line, which uses a taller bottom track gasket than the window lines. If a homeowner swaps a weatherstrip from a 200 series window into a 300 series door, it will look fine for about three weeks, then the first heavy rain pulls water under the sill. That’s the compatibility gotcha to know.
Flashing kits and perimeter sealant details also differ by rough-opening depth. A wood-framed ADU wall with 2×4 construction takes a thinner jamb receiver than a 2×6 exterior wall. If you’re pulling a serial number from the frame, look for a small white sticker on the top edge of the fixed sash, or on the head jamb above the sliding panel on the doors. The first three digits of the serial tell us the series. When OEM parts are available, we spec OEM. When lead times run long (which happens on some ECO patentry door hardware), we’ll offer a quality aftermarket equivalent from brands like Truth Hardware or Roto, and we’ll tell you before we order, not after.
Styles & brands we work with
Signs Your ECO Window Systems Home Additions & ADU Is Failing
- Water staining on interior drywall below a window or door corner. This almost always means the sill flashing or the bottom track gasket has failed. It shows up first at the corners because that’s where the frame welds meet and water has a path.
- A door or window that locks hard, or the handle won’t engage at all. San Antonio’s soil shifts, and once the rough opening moves out of square by even 3/16″, the locking points stop aligning. The hardware isn’t always the problem; the opening is.
- Condensation between the glass panes. That’s a broken thermal seal. It never heals, and it gets worse every summer. We see it on east- and west-facing glass faster because the sun hammering the frame accelerates the sealant aging.
- A sliding patio door that scrapes or drags after a big freeze. Some ECO tracks are aluminum, and when they’re not shimmed with a thermal break, the contraction pulls the track gutter down just enough to catch the rollers.
- A window that creaks when the wind pushes against it. Usually a loose glazing bead or a corner weld that’s started to separate. Ignore it long enough and the outer pane loses its compression seal.
See the difference
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After
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After
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AfterReplacement Cost & What’s Included
For the parts themselves in a San Antonio addition or ADU, here’s what we typically see installed:
- Replacement weatherstripping on an ECO-200 window: $40 – $120 per window
- New multi-point locking assembly on an ECO patio door: $180 – $420
- Full hardware set (rollers, handle, track gasket) on an ECO sliding door: $350 – $700
- Replacement insulated glass unit (IGU) in an ECO frame: $250 – $700 per sash depending on size and low-E coating
- Full multi-panel glazing swap and re-flashing on a small addition window set: $2,000 – $6,500
The range comes down to frame extraction difficulty, whether the original installer back-flashed correctly, and how much drywall or trim we have to cut to access the sill. Labor in San Antonio runs $75 – $110 an hour for this kind of work, and a simple hardware swap is usually 1 – 2 hours. A full IGU replacement with re-bedding and trim work is more like a half-day. Every part we install carries our 365-Day Done Right Promise: if it’s not done right, we make it right, in writing. Every repair gets a written price before we touch anything.
DIY or Call Us?
You can safely check two things yourself: look for the window serial sticker I mentioned above, and snap photos of the water stain or failed part before anyone shows up. That saves you a trip charge and gives us enough to pre-diagnose. Beyond that, I’d be cautious. Anything involving removing a frame, extracting an IGU, or adjusting a multi-point lock under tension can go sideways quickly, especially on ladders or upper floors of an addition. We’ve also seen more than one homeowner strip an ECO frame weld trying to force a stuck lock, and that turns a $150 hardware fix into a full sash order.
If the part is loose hardware, a torn weatherstrip you can access from inside on a first floor, or a handle that’s clearly broken, you can likely handle it with the right part. If there’s water, air, or glass involved, call us at (432) 547-6806. The free estimate applies to this too.
FAQs
Most weatherstripping and gaskets on these units last 5 – 8 years in our climate before UV and heat compromise them. The frames themselves often last 20 – 30 years if the original install was flashed correctly and the rough opening doesn’t shift. Call (432) 547-6806 and we can tell you exactly what’s in yours before you spend a dime.
A failed thermal seal cannot be permanently repaired, but the glass unit can be replaced without replacing the entire frame. We order a new IGU matched to the original low-E coating and thickness, then reset it in the existing frame. So you keep the original Eco Window Systems look but get a new sealed unit, and the whole job is usually done in one visit.
For hardware and weatherstripping, most jobs are done in under two hours once we’re on site. A full IGU replacement or a track assembly replacement is a half-day, including cleanup and trim reinstatement. We’ll tell you the window of time before we show up, and we give you photo updates while the work is happening if you can’t be on-site yourself. Call us at (432) 547-6806 for a specific timeline on your part.
We keep the most common ECO hardware, rollers, and weatherstrip profiles on our trucks because we serve San Antonio, Alamo Heights, Terrell Hills, and the surrounding metro, and those are the parts that fail most often. For glass units and specialty locking assemblies, we order direct from our supplier network, which usually gets the right part to us within a few days. And if you also have cabinetry from KraftMaid, or Cambria or Silestone countertops elsewhere in your addition, we work across those too, so one call covers it.
For a written estimate on any ECO Window Systems part or home additions and ADU work in San Antonio, call (432) 547-6806. A live person answers, and we’ll get your part priced before we step on-site. The craft comes first. Everything else follows.
Written by Luca Romano, Owner, Sawyer Remodel San Antonio at Sawyer Remodel San Antonio, serving San Antonio and nearby areas.
