Don’t be left out in the cold on Part L

Posted On 21-08-31

“New rules, designed to improve the standard of energy efficiency in homes are due to be unveiled this Autumn,” says Ian Cocken, Director of Sales and Marketing, aluplast.

“The UK has ambitious targets to meet on climate change, but it is lagging behind on these goals and it needs to introduce more impactful measures to get back on track.

“That is likely to mean big changes to Part L of Building Regulations in order to improve the minimum energy efficiency rating of windows and doors into new build as well for the home improvement sector,” he continues.

“It’s a big change, and it has the potential to cause some real problems for companies who rely on the performance of older products that may already struggle to meet current energy efficiency requirements, let alone satisfy any future standards.

“That includes PVC but especially aluminium systems, which are typically much less thermally efficient,” adds Cocken.

Ian Cocken, Director of Sales and Marketing, aluplast UK

The Ministry of Housing Communities and Local Government (MHCLG) is set to publish its revisions to Part L in October, changes that would come into force as early as Spring 2022.

The proposals are expected to include setting a new maximum u-value for replacement windows of 1.4W/m2K or WER B from the existing C rating and 1.6W/m2K maximum u-value.

For replacement doors, it is anticipated that the minimum DER will be changed from 1.8W/m2K to 1.4W/m2K, or DER B and E to Band B; or doors where the glazed area is greater than 60%, 1.8W/m2K to 1.4W/m2K or a DER Band C rating. For new build, the proposed revisions are set to be even stricter.

“It’s a difficult time for the industry because everyone is currently working flat out just to keep up with demand,” Ian continues. “But these changes are just around the corner and anyone who doesn’t take the time to understand the impact they will make across the supply chain runs the risk of being caught out.

“Introducing a higher specification IGU may help, but that’s more of a quick fix. Fabricators should be looking for more of a long-term solution, especially if they want to stay ahead of even stricter standards in the future.

“Ultimately, that could mean investing in a newer, better performing product range,” says Ian. “Our Smart-Slide system for instance, presents a number of advantages, and not just as a class leading PVC system. Thanks to its technical performance, the size at which it can be manufactured and its contemporary aesthetics, it also makes a highly compelling – and much more energy efficient – alternative to aluminium.”

Designed to meet BS6375 for weather tightness and a DER of A+ depending on glass specification, Smart-Slide delivers U values as low as 1.3W/m2K, comfortably below the proposed new Part L requirements.

Key to this is an advanced profile design and the use of high-quality hardware. Offered with PAS24 as standard, the elimination of brush seals allows Smart-Slide to be operated with just the lightest of touches, even with sash weights of up to 200kg. It also locks on all four sides of the sash, allowing the door to be left part open but still remaining completely secure.

Smart-Slide can also be manufactured to span 4.5m at 2.5m with just a sliding sash and a panel, significantly larger than traditional PVC patios that that would typically be limited to a maximum pane size of 2.1m x 1.8m.

This design flexibility, argues Cocken, combined with the range and quality of finishes available from aluplast, presents a unique opportunity for its customers.

“Installers are already at an advantage with Smart-Slide because it’s very easy to demonstrate the quality of the system over competitor PVC products,” he says. “Optioned with a smooth grey finish, or one of our next generation aludec foils, and you really would struggle to tell the difference between a Smart-Slide install and one that’s made from aluminium.

“The only difference of course, is that it doesn’t cost as much as aluminium and it delivers much better energy efficiency. That’s already a strong proposition for installers at point of sale – but it will become an even stronger one when the new rules on Part L come into force early next year,” he concludes.

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