
Shootbolt security locking
Secured by Design accredited shootbolt locking with BSI-tested security criteria and a 10-year mechanical guarantee on every installation.

Windows
The most popular window style in the UK, side-hinged sashes that open outward for excellent ventilation and a clean, versatile look.
Personalise Your Window
Frame Colour: Smooth White
Standard colours
Extended lead time colours
Dual colour available, different interior and exterior finishes on request.
Hardware Finish: White
Handles, letterplates, and accessories available in matching finishes.
Made to measure. Confirm your colour and hardware choice during your free survey.

Free Survey
If this looks like the right fit, we can survey the opening, confirm the specification, and price it properly for your home with no obligation.
Casement windows are the most widely installed window style in the UK, and for good reason. Their side-hinged sashes open outward, providing excellent ventilation while maintaining a clean, uncluttered look from inside and out. CII Double Glazing supplies and installs uPVC casement windows across Romford and Essex, using 70mm multi-chambered profiles that achieve A+ energy ratings with U-values from 1.3 W/m²K with double glazing, or 0.9 W/m²K with triple glazing. Our directly-employed installation team handles everything from survey to sign-off. No subcontractors at any stage.
10-year profile guarantee. No warping, splitting, or discolouration
10-year mechanical guarantee on all locking hardware
£7,500 break-in protection promise
Stay Guard Elite hinge protection, twice Secured by Design test force
Stainless steel friction stays tested to 20,000 cycles
100% lead-free, recyclable uPVC. BSI Kitemark certified
Engineering Detail

Secured by Design accredited shootbolt locking with BSI-tested security criteria and a 10-year mechanical guarantee on every installation.

Hinge protection that withstands twice the force required by Secured by Design testing, providing exceptional resistance to forced entry at the hinge side.

70mm EnergyPlus profiles with multiple thermal chambers that trap warm air within the frame, achieving A+ energy ratings and U-values from 1.3 W/m²K.

Optional triple glazing brings U-values down to 0.9 W/m²K for north-facing rooms or exposed elevations, significantly reducing heating bills.
How It Works
Step 1
We visit, measure, and advise on the right configuration for your property.
Step 2
Our directly employed team installs with clean, tidy workmanship.
Step 3
Final checks, handover, and Assure certification where required.
Next Step
We will measure up, talk through finishes and installation details, and give you a clear quote based on the actual opening rather than a generic estimate.
“Fantastic experience from initial survey to completion. The team were professional, tidy, and the attention to detail on the finish was fantastic. Couldn't be happier with our new windows.”
“Used CII for our entire house of windows. Brilliant from start to finish. Knowledgeable, reliable, and very professional. The quality of the product and installation is second to none.”
Questions Answered
Where We Work
Based in Romford, we regularly work across Essex, North and East London, and into Hertfordshire. If you are not sure whether we cover your area, just give us a call.
Find Us
Phone
020 8500 9100Hours
Mon to Fri, 8am to 6pm
Free home surveys available across our coverage area.
Areas We Cover
View all local area pages or not seeing your area? Get in touch and we will let you know if we travel to you.
Get Started Today
Get a free, no-obligation quote from our team. We survey, advise, and install. All handled directly, no subcontractors.
Mon-Fri 8am-6pm · No call centres · Speak directly with Ross
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