Our Vertical Slider is a classic design

Published: 10th May 2017

Martin Althorpe, Technical Director at Spectus Systems, celebrates the Spectus Vertical Slider that has led the way in heritage design for many years and looks set to maintain its status for many more to come.

Seventeen years ago I was part of the Spectus New Product Introduction team that designed and brought to market a revolutionary new Vertical Slider. I’m incredibly proud that the product blazed the trail for PVC-U in heritage and conservation markets back then. I’m also incredibly proud that it has more than stood the test of time and remains as popular as ever today. More than that, it is still widely recognised as one of the best PVC-U alternatives to traditional timber box sash windows on the market today.

The reason our Vertical Slider is recognised as one of the best is because of its craftsmanship and attention to detail in design. The frame, bead, sash and cill all have an authentic ovolo shape. The window has a deep bottom rail that is specifically designed to replicate the period look of the traditional timber sash. Large and small sash profiles give equal sightlines to the top and bottom sashes for an authentic heritage appearance. The flush gaskets mimic traditional glazing while optional features such as Georgian bars, sash horns, weather bars all complement the traditional feel. A wealth of colours and woodgrain effects to choose from all add to the period beauty.

Yet while the looks may be heritage, the thermal efficiency, security and usability features certainly aren’t. Our Vertical Slider is designed to achieve a Window Energy Rating of Band ‘A’ with 24mm sealed units. Pile seals to the sash and outerframe prevent draughts. Trickle or glazed in vents aid air flow. The window is available in standard or fully reinforced versions and can be customised to meet the highest security standards. The window has smooth operating balance mechanisms for ease of use and both sliding sashes tilt inwards for easy cleaning.

To indicate the quality of the Spectus Vertical Slider system, it is Kitemarked to BS EN 12608, certified to PAS 24. Not only that, we manufacture under a quality management system that conforms to BS EN ISO 9001 and are recognised for responsible sourcing under BES 6001.

The combination of heritage style, cutting edge technological benefits and accredited quality mean the Spectus Vertical Slider is widely approved by planners for use in buildings in conservation areas. It is testament to the quality and authenticity of the system that this is the case.

Of course, as good as a product’s features may be, it is never destined to be successful unless it is embraced by the people who have to work with it every day. It’s something we never forget at Spectus and you can see this in our Vertical Slider. The 128mm outerframe matches the balance box dimensions of the timber sash window, making installation simple. It has 150mm and 210mm cills and 10mm/20mm/50mm frame packers for maximum flexibility. And it is compatible with off the shelf hardware so end users can create a distinctive finish.

The definition of a design classic is something that is always at home in whatever environment it’s put in. I think you can safely call the Spectus Vertical Slider a design classic because it is not only a popular product for period properties, it is also a popular addition to modern homes and new build properties. It means that while it is a product that is perfectly designed for its niche market, it also has a broader market reach. This makes it a very appealing product to have in your portfolio, as so many of our customers know.

A systems house is ultimately judged on its products and Spectus is widely recognised as having the best and most complete range on the market. In products such as our Vertical Slider you can see the elements that are our hallmark: a product that is tried and tested with a design that has stood the test of time yet still remains at the forefront. It’s something we are very proud of.If you require any more information on any of our products please contact

If you require any more information on any of our products please contact 01952 283344 or drop us an email here and we will reply quickly.