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CGI Home Additions & ADU: The Houston Owner’s Guide
Most homeowners searching “CGI home additions” in Houston are actually holding a failed window, door, or framing component from a CGI product line and want to know two things fast: can it be matched, and what will it cost. At Penhallow Remodeling Houston, we install and repair CGI-compatible openings, tie-ins, flashings, and structural surrounds for home additions and ADUs across the Houston metro, with full-project work typically running $45,000–$130,000 depending on the addition’s footprint and how much of the existing CGI envelope needs reworking. The symptom picture is usually straightforward: water staining at a corner, a window that won’t seat flush against the new framing, or a door that binds after the first Houston summer of slab movement.
We’re an independent contractor, not a CGI dealer or affiliate. That matters because our loyalty is to the installation and the weathertight detail, not to moving a specific product line. When a CGI component fails inside a new addition, the problem is rarely the extrusion itself. It’s usually the connection between the CGI product and the new construction: flashing depth, sill slope, rough-opening tolerance, or a tie-in detail that was never detailed for Houston’s clay soils and 50-plus inches of annual rain.
Which CGI Models This Applies To
CGI’s residential window and door lines show up most often in Houston additions and ADUs as impact-rated units specified for hurricane zones, but the compatibility question is less about series name and more about the engraving. Every CGI unit carries identifying marks in the frame corner: a series code, the date of manufacture, and the DP rating. If you can read that corner etch or the original spec sticker, we can usually identify what was installed and what’s currently available as an OEM replacement versus what should be upgraded to a current-generation equivalent.
Two compatibility gotchas we see regularly in Houston. First, older CGI single-hung units from the pre-2015 residential lines occasionally use a non-standard shoe width, which means the new trim and the old rough opening won’t agree unless someone shims and details the reveal carefully. Second, impact glazing ratings are not backward-compatible: a 50 DP window installed 15 years ago cannot be edge-swapped with a 60 DP unit and keep its rating. We source OEM where the rating matters and proven aftermarket equivalents where the original part has been discontinued and the opening only needs weathertight function. For additions and ADUs, KraftMaid casework, Cambria and Silestone surfaces all work cleanly alongside repaired or replaced CGI openings.
Styles & brands we work with
Signs Your CGI Home Additions & ADU Is Failing
- Water staining below a corner of the new window or door. Houston’s afternoon downpours find the smallest flashing gap. If the sill slopes inward or the backdam was never sloped correctly, water tracks down the interior drywall. The fix is almost always a new pan flashing and sill detail, not a new window.
- Interior doors bind during dry months. Clay soil under a new ADU shrinks in drought and swells in wet years. A CGI door that swings true in October and binds in August is a foundation or rough-opening tolerance issue, not a hinge problem.
- Visible gap growth at the trim-to-window interface. PVC and aluminum expand at different rates under Houston’s sun load. If caulk lines keep cracking at the same two corners, the rough opening was likely cut too tight.
- Condensation between glass panes in an existing CGI unit. The sealed-unit gasket has failed. The frame is probably fine; the glass pack can be replaced without pulling the whole window in most series.
- Audible air movement around closed windows during north wind events. That whistle means the weatherstrip or the jamb clearance is off, usually from sagging headers on an undersized lintel.
See the difference
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AfterReplacement Cost & What’s Included
A full home addition in Houston runs $45,000–$130,000. That range is driven primarily by square footage, foundation type, and how much of the existing exterior wall gets opened up. For the CGI-related portion specifically, the repair or replacement of failing window and door openings usually lands between $1,200 and $4,800, which covers pulling the failed unit where needed, correcting the rough opening, installing new flashings, and re-trimming. An ADU with all-new impact-rated openings added to its scope typically runs $90,000–$220,000 all-in, with the opening package as one line item inside that number.
Every price we give is written. It covers demolition, disposal, materials, installation, trim, caulking, and cleanup. No allowance games, no after-the-fact change orders on the line items we agreed to. If the repair fails inside 365 days, we come back and fix it at no charge under the Done Right Promise, and the return visit for a failed repair is free.
DIY or Call Us?
If the issue is drywall staining, loose trim, or caulk that keeps separating, a homeowner can document it and watch it through one rain event. That information helps us enormously and costs nothing. What we don’t recommend is removing the cladding, breaking the interior drywall to inspect a rough opening, or attempting to reset a heavy impact-rated window that has sagged. Those windows are heavy and the glazing is under tension when actively leaking; the moment it’s unseated, two people and proper lift points are required, and Houston’s building code cares how the flashing is layered. Give me the straight story on what you need, and I’ll give you the straight number on what it costs. For anything beyond watching and documenting, call (254) 527-5340.
FAQs
A properly installed CGI unit in Houston should hold its weathertight performance for 20–30 years, with the weak points being sealed-unit gaskets and weatherstrips rather than the frame or glass. Our repair work is guaranteed for 365 days regardless of the unit’s age.
Often yes, supplied the frame itself is sound. Most failing CGI components on Houston additions are repairable at the flashing, weatherstrip, or glazing-pack level, which costs far less than a full unit replacement. Call (254) 527-5340 and we’ll tell you honestly which path makes sense after a site check.
Most CGI opening repairs inside a Houston addition or ADU take one to two working days, including new flashing, trim and interior patch work. A full re-opening with structural lintel work can stretch to four days. You’ll get a written arrival window before we start.
We carry common weatherstrips, sill pans, fasteners, backdams and trim profiles for the CGI residential lines we see most in Houston, and we can source OEM replacement units or glazing packs within a few business days. If it’s a discontinued spec, we’ll show you the current equivalent and the written price before anything is ordered.
Written by Trevor Nash, Owner, Penhallow Remodeling Houston at Penhallow Remodeling Houston, serving Houston and nearby areas.
