Lomax + Wood is the first manufacturer to pass the post in achieving a U-value of 1.1 W/m²K for the Kensington & Chelsea timber sliding sash window. This applies to both traditional weights and pulleys, and spring balance forms of operation. The Kensington & Chelsea flush and stormproof casements achieve a U-value measurement of 1.2 W/m²K, while Kensington & Chelsea French doors perform with a highly satisfactory 1.4 W/m²K. In-house designers at Lomax + Wood continue to work on achieving even better performance.
All measurements have been tested using the new British Board of Agrément (BBA) software tool in compliance with BS EN ISO 10077-1:2006 which has been tested by the British Woodworking Federation to bring its basic U-value calculation service in line with the Construction Products Regulation (CPR). The company’s announcement comes in advance of the 2013 changes to Part L of the Building Regulations, relating to energy efficiency of buildings, which come into effect in April 2014.
While the changes to Part L identify an overall U-value for a building that is dramatically reduced from Part L 2010, specifiers and developers can use a flexible approach as long as the minimum U-value requirements for the individual component parts are met. In effect, this means putting together a mix of different energy-efficient approaches into a modelling software to assess the overall and collective result.
“With Lomax + Wood windows performing outstandingly well, specifiers can utilise our very low U-value windows and doors in the mix which will help offset other materials and systems which are not performing so well,” says Chris Wood, managing director, Lomax + Wood. “This is a great outcome for the company and one that we have worked very hard to achieve.”
The new BBA software tool is based on test criteria of windows and doors manufactured from timber, a natural insulator, that has a density of no less than 500 kg/m³, with a frame and casement thickness of 164mm and 56mm respectively. The 16mm double glazed cavity is Argon gas filled using low emissivity coated glass and warm edge spacer.
Lomax + Wood windows and doors are designed in-house, factory double glazed, with an elegant 20mm wide ovolo glazing bar. They are internally glazed for improved aesthetics, security, and easier maintenance, and fully weather stripped for greater thermal and acoustic performance. All products are supplied with three coats of factory-finished, spray applied micro-porous paint and CE marked.