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CGI Windows & Doors: The Redwood City Owner’s Guide
We stock and install CGI-compatible windows and doors across Redwood City, with most replacement parts available same-day and typical installed pricing running $4,500-$15,000 for full window replacement and $8,000-$25,000 for impact-rated installations. Most Redwood City homeowners discover a CGI part has failed when they feel a draft near a slider they know was shut, or when the lock no longer seats flush after a season of Peninsula morning moisture swelling the frame. The part you need depends on which CGI series is installed, and getting that match right is what determines whether the repair lasts five years or fifteen.
Which CGI Models This Applies To
CGI manufactures several distinct product lines, and the replacement parts are not cross-compatible between them. The Estate Series uses heavier aluminum extrusions with a 2-inch frame depth, while the Sentinel Series runs a slimmer 1¾-inch profile designed for impact ratings without the bulk. The Estate 500 and Estate 2000 share hardware but use different glazing beads, the rubberized strip that seats the glass. The Sentinel by CGI line, common in Redwood City homes built between 2012 and 2019, uses a proprietary roller assembly that looks generic but isn’t, the axle diameter is ¼-inch where standard rollers run 5/16-inch.
To identify your series, check the etched mark in the glass corner or the sticker on the frame edge. If the sticker is gone, measure the frame depth and the roller housing width. We carry both OEM CGI hardware and select aftermarket equivalents that meet the original spec, for rollers and locks, aftermarket is often indistinguishable in performance. For impact-rated glazing beads and reinforced hinges, we source OEM because the certification chain matters for resale and insurance. Rowan Construction Group Redwood City is an independent service provider, not affiliated with CGI.
Signs Your CGI Windows & Doors Is Failing

- The sash drags or sticks in the track. This usually means the roller assembly has flattened or the axle has corroded. Redwood City’s coastal humidity accelerates this, we see it most in west-facing units that catch afternoon salt air.
- Visible gap between sash and frame when closed. The weatherstrip has compressed past recovery or the frame has shifted in its rough opening. In older Redwood City homes with original plaster, seasonal settling makes this worse.
- Lock tongue won’t extend fully or grinds. The internal cam has worn or the keeper has drifted out of alignment. Forced closure bends the linkage, and then you’re replacing the full mechanism, not just adjusting it.
- Condensation between panes. The insulated glass unit (IGU) seal has failed. This cannot be repaired, the IGU must be fabricated to the exact sash dimensions and replaced as a unit.
- Frame corner separates or bows. The thermal break or structural insert has degraded, or the original installation lacked proper shimming. This is structural, not cosmetic, and it worsens fast.
Before
AfterReplacement Cost & What’s Included
For CGI window replacement in Redwood City, expect $4,500-$15,000 depending on unit count, series, and whether impact rating is required. Impact window installation specifically runs $8,000-$25,000, the range reflects the laminated glass, reinforced hardware, and permit documentation for coastal wind zones. Single-part repairs, a roller swap, lock replacement, or weatherstrip refresh, typically fall between $400 and $1,800 installed.
Every quote we write itemizes parts and labor separately. Under Clause 1 of the Haven Standard, that written price is fixed before work starts. No change proceeds without a signed change order. Our 365-Day Done Right Promise covers the installation and the hardware function, if it is not done right, we make it right. The documented photo record you receive shows the condition we found, the parts installed, and the finished operation, included as standard, not an upgrade.
DIY or Call Us?

There is safe owner-checking and there is false economy. You can verify the series label, clean the track of debris, and lubricate the roller with a silicone-based product, never petroleum, it degrades the rubber wheels. What you should not do: remove a sash from a CGI impact-rated unit without support bracing, the glass is heavy and the frame is engineered to carry that load in a specific orientation. We have seen homeowners crack an IGU by tilting the sash wrong during removal. For lock mechanisms, the internal springs are under tension and the small parts scatter when the housing opens.
Our crews carry CGI-compatible rollers, locks, weatherstrip, and glazing beads on the truck. We background-check and uniform every technician, and a live person answers calls 24/7. If you want the part matched right and the operation tested before we leave, call (650) 560-7228 to schedule your free estimate.
FAQs
With proper installation and maintenance, CGI aluminum frames last 20-30 years, but the moving parts, rollers, locks, and weatherstrip, need attention every 7-12 years in this climate. The salt air and UV exposure on the Peninsula degrade rubber faster than inland. Call (650) 560-7228 for an exact quote on your specific units, estimates are free.
Weatherstrip and rollers are replaceable. Locks can sometimes be adjusted if caught early. Failed IGUs and bent frames require full replacement, there is no reliable field repair. We will show you the photo evidence and write you a price for either path before you decide. Call (650) 560-7228 for an exact quote, estimates are free.
Single-component swaps, one roller or one lock, run 45-90 minutes on site. Full sash or IGU replacement takes 2-4 hours per unit, plus curing time for sealants. We schedule so you’re not waiting. Call (650) 560-7228 for an exact quote, estimates are free.
We carry rollers, locks, weatherstrip, and glazing beads for the Estate and Sentinel series. IGUs and full sashes are fabricated to order from measurements we take on site. For same-day roller or lock replacement in Redwood City, we usually have it. Call (650) 560-7228 for an exact quote, estimates are free.
Written by Grant Rowan, Owner, Rowan Construction Group Redwood City at Rowan Construction Group Redwood City, serving Redwood City and nearby areas.







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