ST blog 250522

“How do I ensure I get the right windows at the best possible price project-after-project?”

A guest blog by Sonia Travis, Commercial Sales Manger, NorDan UK Ltd

This was a question I get asked quite often, and my answer is usually the same: talk to our in-house design team as early as possible!

With so much product information now available online, I can understand the temptation for the customer or specifier to self-specify products based on desktop calculations and research.

But my experience has taught me that expert advice up-front, be it for a new build or a refurbishment project, can save a bundle of time, money and headaches further down the line.

Why? Well, let’s start with window sizing.

Just small errors in window sizing, and the need to make retrospective adjustments further down the line can significantly increase the cost of each window.

Getting sizing right isn’t easy, and errors can be based on assumptions or simple miscalculations, and I often see sizing misinformation that stems all the way back to the tender.

I’ve seen numerous examples of window sashes (the opening casements), that are oversized in tender documents, which leads to false interpretations of how the job should be priced.

Tender specifications can be read as ‘gospel’, when sometimes they’ve been cut and pasted without reality-checking, or they’re prioritising meeting standards and performance over what’s needed from hardware.

We ask our windows to do more than just reduce carbon and keep us warm, the hardware also has to keep us safe from falls, our homes secure, and protect us from increasingly extreme weather.

We also have to consider people’s needs; what about older people, or those with disabilities or restricted hand dexterity? Do they need lower or different handles?

Keeping on top of ever changing standards can also be an issue further into projects, particularly changes to energy efficiency and evolutions in environmental compliance.

For example, the home energy efficiency criteria is being updated on June 15th (2022), with new building regulations coming into effect, including Approved Documents F, L & O, with maximum permissible U-Values changing from 1.4 to 1.2 for new build developments.

These changes will serve as a forerunner to the Future Homes Standards, which will come into effect in 2025, and likely see U-Values change again to 0.8.

In general, PVCu, aluminium and composite windows can only achieve a u-value of 1.2 by being triple glazed and most are unable to achieve a u-value of 0.8 full stop. High-quality timber framed windows are a different story. NorDan’s windows are able to achieve a u-value of 1.2 with double glazing, and a u-value as low as 0.7 with triple glazing.

Many windows manufacturers are having to make significant adjustments to their products in order to meet this year’s u-value reduction, with some requiring a complete redesign to meet the anticipated changes in 2025.

At NorDan we’ve met the standards set by Part L for many decades, because our windows are designed and tested to exceed British Standards for weather performance.

You can be sure that NorDan’s systems are fully tested and compliant at any given time, but if you want to be 100% certain on where window standards are at now, or in the future, then our specification team can help.

So please get in touch. We’ve got the knowledge, it costs you nothing, and there’s no obligation to work with us.

To get in touch with our specification team, visit or email

I’m Sonia Travis, the Commercial Sales Manager for the North of England, if you’d like to get in touch I’m at or call me on 07583 051 831

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