As specialist fabricator Mercury Glazing enters their 20th year of manufacturing Vertical Sliding windows, Steve Cross Director of Mercury Glazing discusses why the continuing popularity of sliding sash windows is now part of a wider traditional window revival.

Sash windows have been the hallmark of British homes for centuries and evoke the elegance and period aesthetics like no other window choice.  What was once the default window on heritage and architectural sensitive properties, has now become part of a much wider trend with consumers and developers embracing traditional design across modern properties too.

When we manufactured our first Spectus Vertical Sliding window back in 2002, the white casement window was pretty much the default option when it came to PVC-U products. On launch, the Spectus Vertical Sliding window was ahead of its time and was purposely designed to offer a viable PVC-U alternative to the traditional timber sash window. Fast forward twenty years and the Spectus PVC-U Vertical Slider is the product that most planners and conservation officers now readily accept as a true alternative to timber windows. But what’s interesting to note is the shift in demand into today’s modern homes as the window’s high-end characteristics mean it is more relevant than ever.

As one of the UK’s biggest fabricators of the Spectus Vertical Slider, manufacturing both the welded and mechanically joint versions, our experience in the industry combined with the volumes we fabricate means we have an excellent overview of the trends in the vertical slider market.

Even before lockdown one, we had witnessed a step change in demand for our vertical sliders in modern properties. But this demand has been accelerated with consumers having spent time researching their windows whilst investing in their homes. As a result, they have turned to feature-rich products with high-end detailing to deliver their aspirations.

The broader appeal of the vertical slider, especially in modern homes is encouraging. Consumers and contractors are still seeking traditional window styling with heritage detailing such as sash horns and soft heritage hues.  But by removing the heritage detailing you can also produce a window that offers clean lines and adds immediate aesthetic value for modern properties too.

What’s interesting is the opportunities that projects like these present. New build, modern homes might be considered standard white casement window territory. But as this example shows, using our Vertical Slider offers a way to add greater value to a sale and satisfy consumers’ appetite for these window styles.

Despite the differences in the heritage and retail markets, they both have several features in common. These centre around the modern-day advantages our Vertical Sliders brings. Every Vertical Slider we fabricate has a U value of 1.3/m2K as standard. We see that self-builders, in particular, are interested in the thermal efficiency of the products they choose and the U values play an important part in their decision-making process. The ability of our Vertical Slider to deliver good looks and excellent thermal efficiency is a compelling proposition.

Security is an important consideration too. Our Vertical Sliders meet the requirements of PAS 24:2016 as standard and we also offer an option to upgrade to a Secured by Design version where security is paramount.

It isn’t just the products where our Vertical Sliders makes the difference. When you work with Mercury, you don’t just get high-quality products; you also get the experience of our dedicated internal team who will work with you throughout the buying process regardless of business size.

Since 2020 we have doubled our turnover and remain well on track to continue to meet our ambitious growth strategy over the next four-years. We recently opened a second manufacturing plant in Gloucester, have made a considerable six-figure investment in automation machinery from Haffner and recruited several high-level appointments to our talented team.

The Vertical Slider is and will always be considered a key product for the heritage sector, but the upturn in modern homes and the demand for traditional window appeal has never been stronger.



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