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Casement Window.

Crisp sightlines, A+ thermal performance, and a 14-colour palette. Britain's most-fitted window, manufactured here in the UK to your exact opening.

A+ Energy
PAS 24 Security
30 Finishes
From 1.2 U-Value (W/m²K)

Casement Window

uPVC Window System

Glazing

Double / Triple

Energy

A+ Rated

Security

PAS 24

Frame

30 Finishes

Hardware

6 Finishes

Warranty

10 Year

Classic Outward-Opening Design

The Apex Heritage 2500 casement features sharp yet understated styling with A+ energy rating. Triple glazed options available. 100% recyclable with 10-year manufacturer guarantee.

uPVC Casement Window detail
Agate Grey uPVC casement windows across a full house facade

Engineered for everyday excellence.

Made to measure in the UK. Timeless chamfered design, serious engineering inside — and four good reasons it's still Britain's most-fitted window.

Super efficient

Multi-chamber thermal breaks and warm-edge spacers, A+ rated as standard. Lower bills, every year of ownership.

Built for any home

The chamfered profile reads clean in a Victorian terrace, a country cottage, or a new build — outward sashes sit proud for sharp sightlines.

Sound-proof

Tightly sealed sashes and internally beaded glazing cut external noise. Triple-glazing pushes acoustic performance further still.

Safe & secure

Steel-reinforced sashes and PAS 24 multi-point Yale locking. Engineered to resist the methods burglars actually use.

Specifications

1.2

U-Value (W/m²K)

Excellent thermal efficiency to help reduce energy bills.

PAS 24

Security

Tested to PAS 24:2016 for enhanced protection and peace of mind.

A+

Energy Rating

Top energy rating for maximum performance and sustainability.

Double / Triple

Glazing

Double or triple glazing options for comfort and quiet.

Multi-point

Locking

Advanced multi-point locking for superior security.

100%

Recyclable uPVC

Sustainable by design. 100% recyclable uPVC.

10

10 Years

Guarantee

Backed by our 10-year manufacturing guarantee.

30+

Colours

A wide choice of colours to suit every style.

Technical

Built for performance

Outward-opening sash on a 70mm chamfered profile, standing proud of the frame for traditional sightlines. Multi-point locking as standard. Compatible with 28mm double or 36mm triple glazed units. 100% recyclable PVC‑U with a 10‑year manufacturer guarantee.

28mmDouble Glazing
36mmTriple Glazing
Multi-PointLocking
10-YearGuarantee

Configurations

Flexible design options

Side-hung, top-hung, or fixed options. Available as single or multi-light configurations with Georgian or astragal bar options.

Side-Hung
Top-Hung
Fixed Panels
Multi-LightOptions

Finishes

Made to match your space

20 colourways held in stock, with 30 available across the heritage woodgrain collection. Smooth, grained, and woodgrain foils that never need repainting, with dual-colour options for a different finish inside and out. All finishes carry the same 10-year guarantee.

Black RAL 9005
Anthracite Grey RAL 7016
White RAL 9016
Bespoke RAL Colours

Make it yours.

Selected colour · Agate Grey

White Foil casement window
How long does installation take?

Most window installs are completed in 1-2 days. Doors typically take 1-3 days depending on threshold work. Full-house or multi-room replacements run 3-7 days. We give you a precise schedule at the survey stage so you can plan around it, no open-ended jobs.

Is the installation FENSA-registered, and do I get the certificate?

Yes. Apex Glazing is FENSA-registered (Reg 40373). On completion you receive a FENSA certificate, which satisfies Building Regulations Part L compliance and removes the need for separate council approval. Certificates are issued within 30 days and stored in your FENSA online account for future house sales.

What warranty do I get?

10-year manufacturer warranty on the product itself (frame, glass seal, hardware) plus a 12-month workmanship guarantee from us on the installation. We've been trading since 2005 with 6,340 completed projects and a 5.0-star Google rating, we'll come back if anything's not right.

Do you remove and dispose of the old windows or doors?

Yes, removal of existing units, safe disposal at a licensed waste facility, making good of internal and external reveals, and a thorough final clean-up are all included in the quoted price. There are no extras for skip hire, scaffolding, or waste removal.

Can you match existing windows for a phased replacement?

Yes. We can RAL colour-match the new frames to your existing units, replicate sightlines, glazing bar layouts, and hardware style to keep a phased replacement consistent. Bring photos to the survey, or we'll come and measure the existing windows so the new ones blend in seamlessly when fitted alongside.

Interested in Casement Windows?

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