Casement Windows
Where Craftsmanship Meets Performance
We manufacture a fully bespoke range of timber casement windows, designed to complement a wide variety of properties – from traditional and heritage homes to contemporary new builds. Crafted by our skilled joiners using carefully selected, highโquality timbers, each window offers a harmonious balance of timeless design and durable performance, ensuring longโlasting quality for years to come.
Timber casement windows remain one of the most popular window styles in the UK, and the Derwen Joinery collection includes three principal designs, each tailored to suit different architectural and regulatory requirements.

Have a Project in Mind? Let’s Talk.
ย At Derwen Joinery, we believe every exceptional piece begins not with timber, but with a conversation. We are genuinely interested in your ideas, your questions, and the unique details that will make your project a perfect fit for your space. Understanding your vision is the most crucial part of our craft. Get in touch with us today to discuss your plans and let’s begin the journey of bringing them to life.
Material and Finish Specifications
Many of our windows can be finished using our inโhouse, highโperformance threeโcoat spray system, should you choose this option. Each selected component is fully endโgrain sealed and can be finished in any RAL or translucent colour, with dualโcolour combinations available to suit both interior and exterior design schemes.
For added convenience and reassurance, customers can also opt for factoryโfitted glazing and highโspecification locks and ironmongery from leading hardware manufacturers. These premium components ensure smooth, secure and reliable operation, enhancing longโterm performance.
As energy prices continue to rise, more homeowners are seeking higherโperforming, energyโefficient glazing – particularly in older properties. To support this, we offer a range of advanced glazing options including Vacuum Insulated Glass (VIG), 12mm heritage units and 24mm doubleโglazed units (DGU).

Range of Casement Windows
Traditional Flush Casement Perfect for replacing windows in period homes and traditional properties, this design offers authentic character and understated elegance. Its classic proportions make it a natural choice for heritageโled renovations.
Conservation Casement Developed from our traditional flush casement design, this range meets conservation requirements while preserving the original appearance of the property. Whether you are restoring a listed cottage or working within strict planning conditions, it provides visual continuity while discreetly delivering modern performance standards.
PAS24 Casement A highโperformance option designed for new builds and changeโofโuse projects. These windows offer enhanced security, excellent energy efficiency and full compliance with PAS24 requirements.
Check out our blog!
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