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Unilock Windows & Doors: The Houston Owner’s Guide
Unilock windows and doors typically need repair or replacement when seals fail, hardware wears out, or Houston humidity works its way into frames. Most Unilock window and door service in Houston runs $250 – $850 for parts and labor on a single unit, while full replacement of a Unilock door or window system lands between $1,200 and $4,500 depending on size, glass package, and what’s behind the trim. We stock common Unilock-compatible hardware, weatherstripping, balance springs, and lock sets on the truck, so a single visit usually gets the job done. Homeowners usually discover a failing Unilock part the same way: a window that won’t stay up, a patio door that drags, or a lock that no longer catches cleanly.
Which Unilock Models This Applies To
We work on Unilock sliding patio doors, casement windows, double-hung windows, and their awning window lines. The quickest way to identify your model is to look at the spacer bar printed between the glass panes, usually in one corner. That etching carries the manufacturing date and sometimes the series code. If it’s faded or missing, we measure the visible glass and the frame channel width to match the part correctly. Here’s a compatibility gotcha we run into often in Houston: Unilock changed their balance spring design around 2015. Pre-2015 double-hungs use a 5/8-inch spiral balance with a different shoe than the post-2015 models. Ordering the wrong one means another trip and another week of a window that won’t sit right. On the OEM-versus-aftermarket question, we lean OEM for anything under tension, like balance springs and hinge arms. For hardware and weatherstripping, a quality aftermarket part often matches or exceeds the original at 30 – 50% less. Penhallow Remodeling Houston is an independent service provider, not affiliated with Unilock, which means we stock parts that actually fit, not just what one manufacturer happens to sell.
Styles & brands we work with
Signs Your Unilock Windows & Doors Is Failing
- Window won’t stay open. The spiral balance spring has lost tension or the shoe has snapped. This is the most common Unilock double-hung failure in Houston, where heat cycles accelerate spring fatigue.
- Patio door drags or sticks. Roller assemblies wear flat over time, especially in homes near the Gulf where fine grit finds its way into the track. You’ll hear a grinding sound first, then feel the drag.
- Lock doesn’t catch or stays stuck. The multi-point lock rod drifts out of alignment as the door settles. Houston’s clay soil shifts under slabs, and that movement transfers directly into door frames.
- Condensation or haze between glass panes. The seal around the insulating glass unit has failed. Once the gas escapes and moisture gets in, the only fix is a new IGU or a full sash replacement.
- Air you can feel around the frame, even when closed. Weatherstripping has compressed or dry-rotted. Houston humidity accelerates that rot faster than you’d see in a drier climate.
See the difference
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After
Before
After
Before
AfterReplacement Cost & What’s Included
Single-part repairs on Unilock windows and doors in Houston run $250 – $850, including the part, labor, and the trip. A full patio door replacement typically ranges from $1,800 to $4,500. A complete window replacement sits between $4,500 and $15,000 for a whole-home job, but single-window swaps usually fall between $800 and $2,200. What drives the price up or down: the glass package (double-pane with argon costs more than a basic clear unit), frame material (wood-clad costs more than vinyl), and whether we find rot or water damage once the trim comes off. Every quote includes a written price before work starts, and every repair carries our 365-Day Done Right Promise: if it fails inside a year, we come back and fix it at no charge.
Key Takeaways
- Most Unilock part replacements in Houston: $250 – $850 installed.
- Full Unilock window or door replacement: $1,200 – $4,500 per unit.
- We stock common Unilock parts on the truck for single-visit service.
- Every job gets a written price and a written one-year guarantee.
DIY or Call Us?
There are a few things a homeowner can check safely. Clean the tracks on your patio door. Tighten visible screws on the lock set. Vacuum the sill. Those are good habits and they sometimes buy you another season. But when a Unilock window balance spring has failed, that’s under serious tension. A balance spring holds 10 to 20 pounds of stored energy. If it releases while you’re prying a shoe out, it can take a finger with it. Same goes for patio door rollers: the door itself is heavy glass and aluminum. If you pull the door without releasing the adjuster properly, you’re wrestling 100+ pounds of glass that wants to tip. We’d rather see you call us at (254) 527-5340 and let a uniformed, background-checked technician handle it. Give me the straight story on what you need, and I’ll give you the straight number on what it costs.
FAQs
Most Unilock windows and doors last 15 – 20 years in Houston before seals, hardware, or balance springs need real attention. The heat and humidity here shorten the lifespan of weatherstripping and glass seals compared to drier markets. Call (254) 527-5340 if your unit is nearing that age and showing symptoms, and we’ll give you an honest replacement timeline.
Yes, most individual parts like balance springs, rollers, locks, and weatherstripping are replaceable without buying a whole new unit. The exception is a failed insulated glass seal, which usually means a new sash or IGU. Call us for a free estimate and we’ll tell you which path makes sense for your unit.
Most single-part replacements like a balance spring or roller assembly take 30 – 60 minutes once the technician is on site. A patio door roller rebuild takes about an hour and a half. If we need to order a non-stocked Unilock part, expect 3 – 5 business days before the return visit.
We stock the most common Unilock-compatible balance springs, roller assemblies, lock sets, and weatherstripping on the truck. For less common parts, we source them directly and handle the whole order so you don’t have to measure anything twice. Call (254) 527-5340 and we’ll confirm what we have before we book the visit.
If you’re dealing with a Unilock window that won’t stay put or a patio door that fights you every morning, call (254) 527-5340. Trevor Nash and the crew at Penhallow Remodeling Houston will give you a written price before any work starts, and a written guarantee that covers the repair for a full year.
Written by Trevor Nash, Owner, Penhallow Remodeling Houston at Penhallow Remodeling Houston, serving Houston and nearby areas.
