High-Performance Timber Windows and Doors with
PassivGlas™
Engineered for Modern Living
We’re proud to offer PassivGlas™, a premium glazing system that delivers the perfect balance of performance, sustainability, and design freedom for timber windows and doors.
PassivGlas™ achieves U-values as low as 0.44 W/m²K, providing exceptional thermal insulation that keeps indoor spaces warm in winter and cool in summer. A vacuum layer minimises sound transmission, delivering a quieter, more comfortable environment with UKAS-tested sound reduction up to Rw 41 dB.
● Toughened as standard for strength and safety
● Slimline thickness from just 6.15 mm, ideal for heritage projects, retrofits, and new builds
● Lifespan of 25+ years with minimal maintenance
● Sustainably built to reduce carbon footprints, backed by a 15-year guarantee
● UK-based supply and support for dependable quality and service
Why Derwen Joinery Choose PassivGlas™
Every timber frame deserves glazing that performs as beautifully as it looks. PassivGlas™ combines advanced insulation technology with timeless aesthetics, helping us deliver energy-efficient, long-lasting joinery that meets the standards of today’s homes and buildings.
Whether it’s a conservation project or a high-performance new build, PassivGlas™ provides the clarity, warmth, and reliability to make a difference.
Built for performance. Crafted for comfort. Made to last.
Ask us about PassivGlas™ for your next project and see how this innovative glazing system can enhance the performance and beauty of your timber windows and doors.
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