June 15, 2023

Brave new world

We’ve reached a point of no return when it comes to window and door design, argues Deceuninck Aluminium’s Director Nigel Headford.
The Decalu88 Flush Casement

The latest Part L update, launched last summer, brought the need for even more thermally efficient windows and doors going into newbuild homes and refurbished properties.

June 15th marked the end of the newbuild transition period and all windows and doors supplied to site need to meet the higher standards of performance introduced in last year’s update to Part L.

Windows and doors with a glazed area of more than 60% going into newbuild properties will now need to offer U-values of 1.2W/m2K. For refurbishments, this rises to 1.4W/m2K.

According to Nigel Headford, director of Deceuninck Aluminium, the transition period could not have been more welcome for many fabricators and installers, but it will still leave many aluminium systems companies struggling to meet the new requirements without triple glazing.

“There are a frightening number of older aluminium systems which can’t get down to U-values of 1.2W/m2K without using triple-glazed units, which comes with increased cost and weight, impacting on handling and hardware. It also has ramifications for home improvement because under the regulations extensions are classed as newbuild, so the implications are significant.”

Nigel Headford, Director

According to Nigel, this is starting to have a profound impact on the aluminium window and door sector, as companies reassess their product portfolios and their go-to suppliers.

“For the most part, window companies expected their suppliers to keep up with the ever-tightening Building Regulations, but we have got to a point where we can’t expect a tweak here or a tweak there to keep systems modern, thermally efficient, and compliant,” he says.

Nigel argues that new system designs are required, which means moving away from some long-held beliefs when it comes to dimensions.

The Decalu88 Flush Casement

In response to the broad design brief, Deceuninck Aluminium launched its new ultra-energy-efficient Decalu88 Flush Casement Window in March.

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Deceuninck Aluminium’s Decalu88 Flush Casement

Flush inside and out, it achieves headline U-values of as low as 0.8W/m2K – a Passivhaus equivalent level of performance – and 1.2W/m2k with a standard double-glazed unit.

Designed by a UK design team, the system is built around a patented thermal break which helps to deliver the Decalu88 Flush Casement’s advanced thermal performance. 

In common with the Decalu88 Bi-folding Door, it also features a knock-in glazing bead with a flush finish pre-inserted gasket, saving time in fabrication and on site.

“With the new Decalu88 Flush Casement, we wanted to make compliance a cinch. As such, window companies can adjust their offering by switching out the sealed unit. 

“The fact that it achieves 1.2W/m2K with a double glazed unit, means that it is suitable for newbuild, refurbishment, and those refurbishment projects that incorporate an extension.

“And as we have the Future Homes Standard in our sights, window companies can be confident that the Decalu88 Flush Casement can get down to U-values of as low as 0.8W/m2K with a triple-glazed unit.”

Nigel Headford, Director

Moving away from a standard 70mm frame is key to Deceuninck Aluminium’s success, Nigel says, and it puts the industry on a new path to innovation and design freedom.

“The refurbishment market was the last stronghold for 70mm systems,” he says, “but it is clear that deeper systems allow for greater efficiency and easier compliance. With the Future Homes Standard likely to require U-values of as low as 0.8W/m2K in newbuild homes, we may now be truly in a post-70mm world.”

Deceuninck Aluminium is ahead of this curve, offering u-values as low as 0.8W/m2k across its comprehensive range. 

This includes the Decalu88 Bi-fold, the Decalu163 Lift-and-Slide, and a complete range of casement, tilt-and-turn, fully reversible, steel-type heritage, and now the new Decalu88 Flush Casement. 


For more information call 01249 816 969, email info@deceuninck.co.uk  or visit https://deceuninckaluminium.co.uk/products/windows/decalu88-flush-casement/  

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