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ECO Window Systems Home Additions & ADU: The Houston Owner’s Guide
Penhallow Remodeling Houston installs and services ECO Window Systems-compatible home additions and ADU projects throughout the Houston area, with a typical installed price of $45,000 – $130,000 depending on square footage, foundation work, and the window package you choose. Most homeowners reach out to us in one of two ways: either they’re planning a new build and want the addition or ADU to match their existing ECO Window Systems performance, or they have an existing structure where the windows are failing and the frame around them is starting to go with it. The symptom picture is usually the same: condensation that won’t clear, a window that won’t lock flush, or drywall cracking at the corners of an addition that was never tied into the main structure correctly.
Which ECO Window Systems Models This Applies To
ECO Window Systems produces several series lines, and the compatibility question matters before a single stud goes up. The ECO 3000 series is an aluminum thermally-broken frame used widely in Houston additions from the early 2000s onward, while the ECO 5000 vinyl series shows up in more recent ADU builds. They are not interchangeable. The 3000 series uses a 2-1/4″ frame depth; the 5000 runs 3-1/4″, which changes your rough opening and your trim treatment. If you have an addition built between roughly 2005 and 2015 in Houston, there’s a good chance you’re looking at the 3000 series with the older glazing bead, which ECO has since revised. The tell is the corner joint: the older 3000 series has a visible mechanical fastener at each corner, while the revision uses a crimped, cleaner corner. If you need the part that joins two window units together in a large addition or ADU opening, that’s an ECO-specific mullion connector, and we stock both the original profile and the current one. We are an independent Houston contractor, not affiliated with ECO Window Systems, which means we can tell you plainly when the OEM part is worth the money and when a quality aftermarket equivalent performs just as well without the brand markup.
Styles & brands we work with
Signs Your ECO Window Systems Home Addition or ADU Is Failing
- Condensation between the glass panes. That’s a failed seal in the insulated glazing unit. The argon or krypton gas has escaped and moisture is working its way in. Once the seal fails, the window’s thermal performance drops and the glass starts looking permanently fogged in the morning. In Houston’s humidity, this failure happens faster than in drier climates because the air pressure difference across the glass is greater.
- The window binds or won’t close tight at one corner. That’s often not the window at all. It’s the addition settling. Houston’s clay-heavy soils around Meyerland and other areas expand and contract with moisture, and a footing that wasn’t sized for that movement will shift a window rough opening out of square over time.
- Drywall cracks at the seam where the addition meets the original house. This is the classic sign of a cold joint, where the new framing wasn’t tied into the existing structure with enough mechanical connection. The two structures move at different rates and a crack opens up at the joint. That crack isn’t cosmetic; it’s telling you about the connection quality behind it.
- Water staining below the window on the interior drywall. In Houston, this often traces to an improper flashing detail at the head of the window. ECO frames have a specific drainage path designed into the frame profile, and if the installer used a generic flashing tape over the top instead of the product-specific flashing detail, water picks the path of least resistance: into your wall cavity.
- The window is loose in the rough opening with visible gaps where shims should be. That usually means the installer relied on foam instead of properly set shims, or the shims were set at the wrong points for an ECO frame. The frame’s reinforced points, not the corners, carry the load, and a window set on corner shims will eventually drift and bind.
See the difference
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After
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AfterReplacement Cost & What’s Included
A full home addition or ADU project in Houston runs $45,000 – $130,000, and the window package is a line item worth understanding before you’re handed a number. If you’re replacing failing windows within an existing addition, expect window replacement work in the $4,500 – $15,000 range depending on how many units and whether the surrounding framing needs repair. The factors that drive cost on the addition side are straightforward: foundation type (slab is common in Houston but pier-and-beam still exists in older neighborhoods like Meyerland), whether the roof structure ties into the existing roof or stands as a separate plane, the window count and series, and the interior finish standard. We give you a written price before any work starts, not a range with a wink. Every line item is explained face to face, and if it’s not done right, the 365-Day Done Right Promise brings us back at no charge. That promise is in writing on every project, and it’s part of The Kingswell Way: say the price before the work, show up in the window we gave, leave the place cleaner than we found it. Materials come from brands we trust, and when an owner wants a specific window line in an addition, we’ll spec it correctly the first time because failing windows in a two-year-old ADU is a phone call nobody should have to make.
DIY or Call Us?
Let me be straight about where this job splits. If you have a single failing window within an addition and the rough opening is still square, a careful homeowner can sometimes swap the sash or replace the glazing unit, and that’s fine. But if the issue involves wall framing, foundation movement, or removing the entire frame from an ECO Window Systems opening, call us. Window and addition work sits at the intersection of structure, flashing, and waterproofing, and Houston’s climate punishes any gap in that chain. You don’t want to find out six months later that the leak was from a flashing detail you improvised. Give me the straight story on what you need, and I’ll give you the straight number on what it costs. Call (254) 527-5340 to schedule a free estimate.
FAQs
In Houston, an ECO Window Systems window in a properly installed addition should hold up 15 to 25 years before the seals start losing gas, but the frame itself can last much longer if it was set correctly. The Houston humidity accelerates seal failure compared to drier markets, so if you’re at year 15 and seeing fogging, you’re on the normal end of the curve. Call (254) 527-5340 to schedule a free estimate and we’ll inspect the whole window package, not just the obvious failures.
Yes, in many cases the insulated glass unit can be replaced while keeping the original ECO frame in place, which costs less than a full window replacement. If the frame is still square and the hardware isn’t worn out, swapping the glass unit is the better value. If the frame has shifted or the drainage channels are compromised, replacement is the honest answer. Call (254) 527-5340 and we’ll give you a straight recommendation.
A typical Houston home addition runs 3 to 6 months from permits to final walk-through, while an ADU in the $90,000 – $220,000 range usually spans 4 to 8 months depending on foundation work, utility runs, and the window package. If you’re only replacing windows in an existing addition, most jobs finish in 1 to 3 days. We’ll give you a written schedule and a real arrival window before we start, and the person who answers the phone knows the status of your job. Call (254) 527-5340 to get exact timing for your project.
We carry the common ECO Window Systems parts on our trucks: mullion connectors for both the 3000 and 5000 series, replacement glazing beads, and the current hardware sets, so most window repairs within an existing addition or ADU don’t wait on a parts order. If the part you need isn’t standard, we’ll get it ordered and give you a straight answer on when it’ll arrive. We also stock parts for other brands we work with, including KraftMaid, Cambria, and Silestone products that often show up in these additions.
Written by Trevor Nash, Owner, Penhallow Remodeling Houston at Penhallow Remodeling Houston, serving Houston and nearby areas.
