Drawing Board Dedication

Deceuninck’s director, Nigel Headford, says a dedication to repeatedly going back to the drawing board has paid dividends, following the launch of the Decalu88 aluminium casement window. We report.

Since launching the Decalu88 bi-folding door in 2019, Deceuninck Aluminium has developed its product range, incorporating an entrance door, a lift and slide door and windows for light commercial and high-end architectural applications.

They all benefit from the Decalu modular design.

“A key attraction was the uniform appearance,” says Headford. “Today’s market is dominated by homeowners specifying high-end products that suite across a whole project. As a result, we always knew that we needed a casement window – we needed to be able to offer that full suite of products.”

However, Headford says Deceuninck’s aluminium branch didn’t want to be rushed, even if some prospective customers weren’t ready to commit until the systems company had a casement window in place.

He says: “So, we sat down with our R&D guys and got them to really understand what we needed – what our customers wanted and what our customers’ customers wanted.”


Flush inside and out

Headford adds: “Having already worked closely with fabricators and installers, we knew they were sold on the ease of production, the pre-inserted gaskets and the glazing bead. Yet we still went through a long design period, coming up with 49 different variations of the product, before we came up something that was flush/flush – flush on the inside, flush on the outside – and was easy to fabricate.”


Thermal efficiency

One challenge was the thermal performance, especially since the Decalu88 bi-folding door had won many plaudits for being one step ahead of the building regulations.

“How do you design an open-out casement window that performs to – and exceeds – the new regulations?” Headford asks. “And can it be done with a 400mm drop with an 88mm deep window?


Supply chain consultations

Headford answers his own question: “This meant working with hardware manufacturers and other suppliers at a very, very early stage, to ensure that our window worked.”

Another part of the design brief was to design just one window, which can go into newbuild and perform at one U-value and go into refurbishment projects and perform at another U-value.

“Traditionally, you would have a basic window design and add elements that would allow it to perform at a higher level,” says Headford. “But we just decided to make a top performing window and if you needed to enhance it further, you could just change your glass specification.

“That way, you don't have to worry about what your window is costing you. You've got a simple cost base and you don't have to worry about getting additional parts, which fits our philosophy of reducing stock holding and making life simpler for both fabricators and installers.”


Top U-value

The result is a headline U-value of 0.8W/m2K, achievable in a triple-glazed configuration.

It can also achieve a U-value of 1.2W/m2K with a double-glazed unit with a centre pane U-value of 1.0W/m2K, which means it will meet Part L requirements for newbuild, double glazed. And with a ‘standard unit’ with a centre pane U-value of 1.2W/m2K it’s 1.4W/m2K, which meets Part L requirement for home improvement.


Getting into the groove

“Since our customers predominantly fabricate PVC products alongside aluminium, we wanted to incorporate a true PVC groove within our product but we didn’t want a groove all the way around the frame,” Headford says. “So, we designed a patented solution that allows you to expose the eurogroove when you need it but hide it when you don’t.

“This means the window profile is flush on the outside, flush on the inside - and flush inside the window frame.”


Future Homes Standard

With the Future Homes Standard on the horizon, which is expected to demand window U-values of 0.8W/m2K for newbuild homes, Headford concludes that spending the extra time in the design stage for the new Decalu88 casement window was worth it.

“I like to think we’ve turned up the design element to ‘11’ – giving customers exactly what they wanted and a little bit more,” Headford concludes.


Picture: The Decalu88 aluminium casement window has been backwards and forwards on the drawing board until it was right says Nigel Headford.


Article written by John Roper
17th July 2023


Related Articles