Lignum Casement window achieves market-leading weather & security performance

Independent lab testing has confirmed that the Lignum timber Side and Top Swing Casement Window delivers exceptional weather and security performance, placing it among the top-performing casement systems in the UK, across all materials

Led by Owen Dare, Technical Director at TJN, Lignum – The Joinery Network’s timber window and door system – is subject to a continuous programme of development and testing, including new products, updates and enhancements. For all Secured by Design (SBD) audits and test processes, TJN works in partnership with ERC Testing and CenSolutions.

The first Lignum timber Side and Top Swing Casement Windows have now completed full BS 6375-1 weather performance testing, alongside PAS24:2022 (2024) security assessment. The test programme also introduced a new fixed sash option for glazed panels, further enhancing the Lignum range.

TJN Lignum window test

Proven performance under extreme conditions

The Lignum casement recorded significant gains across every key performance category:

• Watertightness (BS EN 12208): Improved from 250Pa to 600Pa, achieving Class 9A, the highest classification, with zero water ingress. This represents resistance to wind-driven rain equivalent to approximately 70mph, up from 45mph.

• Wind Resistance (BS EN 12210): Achieved Class C5, the highest pressure classification.

• Air Permeability (BS EN 12207): Achieved Class 4, the highest level possible.

  
  

Alongside its weather performance, the system also passed PAS24:2022 (2024) security testing, meeting the latest enhanced security requirements without compromising performance or design.

Lignum Conservation Casement

The new Lignum Conservation Casement Window, featuring traditional butt hinges, has also successfully completed PAS24:2022 (2024) testing with both top- and side-hung sashes. Impressively, the required security performance was achieved without the need for hinge bolts.

TJN Lignum double door test

Lignum double doors – open out

The Lignum open-out double doors also achieved PAS24:2022 (2024) certification and demonstrated further improvements in weather performance:

• Air Permeability (BS EN 12207): 600Pa, Class 4 – the highest rating.

• Watertightness (BS EN 12208): 600Pa with zero leakage, achieving Class 9A, the highest possible classification

• Wind Resistance (BS EN 12210): Improved to 1,200Pa, Class A3, the highest level for this configuration.

  
  

“These test results aren’t incremental improvements – they’re a genuine step change for members,” said Owen Dare. “The Lignum casement sets a new benchmark and now sits at the very top of the market, not just for timber, but when measured against high-performance PVC-U and aluminium systems as well.

   “The new Lignum Conservation Casement extends the options for property owners seeking traditional design combined with the latest high-security performance. It’s excellent news for The Joinery Network manufacturers. “The re-testing of the Lignum doors was particularly impressive, and I am extremely proud of the results.”

Further testing is already underway to extend certification across the wider Lignum window and door range, supporting the continued growth of The Joinery Network of Lignum manufacturers.

For further information on The Joinery Network, its Lignum and other products, call 0333 344 9895 or visit the website: www.thejoinerynetwork.co.uk.