CGI Windows & Doors Nationwide

CGI Windows & Doors: The Cupertino Owner’s Guide

We stock and install CGI-compatible windows and doors across Cupertino, with most replacement hardware and full-unit swaps quoted in writing before work starts. Typical installed replacement runs $4,500-$15,000 for standard window units, with hardware-only repairs starting lower depending on the series and access. Same-day parts availability applies to common CGI hardware failures we carry on our trucks in Santa Clara County.

Call (669) 202-9618

Most Cupertino owners discover a CGI part has failed when the sash won’t stay open on a warm afternoon, the multipoint lock won’t engage before a trip, or they notice the frame gap widening after a wet winter in the Monta Vista hills. The Santa Clara Valley’s dry summers and occasional driving rain test the weatherstripping and roller systems harder than the coastal side of the range.

Which CGI Models This Applies To

CGI manufactures under several series lines, and the part you need depends on which generation is installed. The Estate Series uses a heavier extrusion with a distinct bulb-style weatherstrip channel, while the Sentinel Series carries a slimmer profile and a different roller pocket dimension. The Impact Series, common in Cupertino homes built after 2015 for Title 24 compliance, uses reinforced interlocks that do not interchange with standard Estate hardware. Check the etched marking on the glass spacer or the sticker inside the frame jamb; the series code and manufacturing date tell us which roller, lock, or keeper to bring.

We source OEM CGI hardware where the part is still in production, and we vet aftermarket equivalents from Truth Hardware and Amesbury for discontinued lines. The aftermarket route saves roughly 15-25% on hardware-only jobs, but we won’t install an equivalent that hasn’t been cycle-tested in our shop first. Rowan Construction Group Cupertino is an independent service provider, not affiliated with CGI.

Signs Your CGI Windows & Doors Is Failing

• Sash drops or won’t stay open. The balance system, either a coil spring or block-and-tackle unit depending on CGI series, has lost tension. In Cupertino’s dry climate, the lubricant dries and the spring coils fatigue faster than in humid regions.
• Lock handle turns but bolt doesn’t throw. The multipoint gearbox has stripped or the connecting rod has slipped its clip. This is a security issue, not just a draft issue, because the inactive locking points no longer engage.
• Rolling resistance or grinding when sliding. The tandem roller assembly has flat-spotted or the axle has corroded. Hillside homes in Cupertino with exposed exposures see this earlier due to dust and temperature swing cycles.
• Visible daylight between sash and frame. The pile weatherstrip has compressed or the fin seal has torn. Once the seal fails, the thermal performance drops and the frame edge can wick moisture during wind-driven rain.
• Condensation between glass panes. The insulated glass unit (IGU) seal has failed, allowing argon escape and moisture ingress. This cannot be repaired; the IGU gets replaced as a sealed assembly.

Before

After

Replacement Cost & What’s Included

Hardware-only repairs for CGI windows and doors in Cupertino typically run $180-$650 installed, depending on whether we’re replacing a single roller or a full multipoint lock set. Full sash or frame replacement moves into the $4,500-$15,000 range for standard sizes, with impact-rated IGUs at the higher end. We break every quote into line-item parts, labor, and any finish touch-up, with the written price delivered before anyone picks up a tool. Under Clause 1 of The Haven Standard, that number does not change unless you sign a change order. Our 365-Day Done Right Promise covers the installation and the hardware function; IGU seal failure carries the manufacturer’s glass warranty.

DIY or Call Us?

An owner can safely check the series marking, photograph the failed part, and confirm the symptom. What goes wrong fast is forcing a seized multipoint lock, which can snap the internal cam and convert a $200 hardware swap into a full mechanism replacement. The coil balance systems in CGI’s older Estate units carry residual tension; releasing them without a winding tool can cause the bracket to release suddenly. We carry the correct tools and the specific rollers, keepers, and gearboxes on our trucks. Call (669) 202-9618 to schedule your free estimate, and we’ll bring the right part the first time.

FAQs