Vertical Sliding Windows Made to Measure and Built to Last
Flush Sash UPVC brings you the vertical sliding window that replicates the classic sash look with modern uPVC or aluminium performance. Whether you’re restoring a period property or adding a slimline modern slider, every window is made to measure and installed with precision.
- Dual-function tilt and turn mechanism in every window
- PAS 24 & Secured by Design security as standard
- 10-year guarantee for complete peace of mind
25+ years in business
Certified installers
1000+ Home installations
10 Year guarantee
What Is a Vertical Sliding Window?
Vertical sliding windows are a modern take on the traditional box sash window, designed to reproduce the proportions and character of a period timber sash while offering the convenience of a modern replacement. Instead of opening outward like a casement window, the sashes sit one above the other and move vertically within the frame.
They are particularly suited to period properties where maintaining the traditional appearance matters, but they can also work well on homes looking for a slimline, distinctive window style. With made-to-measure sizing, traditional detailing and a choice of modern materials, vertical sliding windows combine heritage character with contemporary performance.
How Do Vertical Sliding Windows Work?
Each sash is held in place by balancers, using a spring or counterweight mechanism that allows the window to stay where you leave it. You can raise or lower the sash to control ventilation without needing a prop, stay, or outward-opening mechanism.
Vertical sliders can be single-hung, where only the bottom sash moves, or double-hung, where both the top and bottom sashes slide independently. Double-hung designs are particularly useful for ventilation because opening both sashes can encourage warm air to escape through the upper opening while cooler air enters through the lower section.
The Key Details That Make a Vertical Slider Look Authentic
The appearance of a vertical sliding window depends heavily on its detailing. Sash horns, deep bottom rails and Georgian bars can reproduce the proportions and visual character associated with traditional timber sash windows, helping modern replacements sit naturally within period elevations.
Sash horns provide traditional detailing at the upper corners of the lower sash, while a deeper bottom rail helps maintain the proportions of an original sash. Georgian bars can also be incorporated across the glazing where a multi-pane appearance is required, giving homeowners more control over how closely the finished window reflects the property’s existing character.
How Do Vertical Sliding Windows Perform?
The traditional appearance does not mean compromising on everyday performance. Modern vertical sliding windows can incorporate multi-chambered profiles, weather-pile sealing and modern glazing systems to help reduce heat loss and draughts around the moving sashes.
The combination of the frame, seals and glazing can also help reduce outside noise, particularly when replacing older or poorly fitting timber sash windows. The exact performance depends on the selected window, glazing specification and installation, so these options can be discussed during the design and survey stage.
Why Choose Flush Sash UPVC?
Choosing the right vertical sliding window is only part of the project. Accurate surveying, made-to-measure manufacture, professional installation and dependable aftercare all contribute to the finished result.
- 10-Year Guarantee included as standard for every product and installation.
- Made in Britain vertical sliders manufactured by the in-house team.
- FENSA Registered certified windows and doors manufacturer, supplier and installer.
- 25+ Years in Business established experience across window installations.
- 1000+ Home Installations experience across residential projects.
- Certified Installers professional installation from survey through to completion.
Start your Project Today
Take the first step towards a more comfortable, secure, and better-looking home. Whether you’re replacing a single window or upgrading your entire property, our team makes the process simple from start to finish. You’ll get expert advice, tailored designs, and clear pricing with no pressure.
Colours
Hardware
Obscure Glass
Glazing Options
Colour and Styling Options
Vertical sliding windows come in classic, woodgrain and modern colours to suit your home.
Traditional details such as sash horns, deep bottom rails and Georgian bars retain their authentic character. Choose a finish that complements your property’s age, architecture and style.
Hardware for Vertical Slider Windows
Our vertical slider windows are finished with carefully selected hardware that combines traditional character with modern functionality. From classic sash locks and pulls to discreet restrictors and sash eyes, every detail is designed to complement the style of your home while providing smooth, reliable operation.
Glass Choices for Privacy and Natural Light
Choosing the right glazing can transform how your rooms feel and function. We offer a range of decorative, obscure, and specialist glass solutions that help balance privacy, daylight, aesthetics, and security while complementing the architectural style of your property.
Advanced Glazing for Better Performance
Modern glazing technology plays a major role in comfort, efficiency, and noise reduction. Our glazing solutions help create a quieter, warmer, and more energy-efficient home while supporting long-term performance and reducing heat loss throughout the year.
Triple
Glazed
Laminated
Glass
Square
Lead
Diamond
Lead
Internal
Georgian Bar
Choosing Between uPVC and Aluminium Vertical Sliding Windows
Choose between low-maintenance, cost-effective uPVC and strong, slimline aluminium vertical sliding windows. Both offer traditional sash styling with a range of colours and finishes to suit your property.
uPVC Vertical Sliding Windows
uPVC vertical sliders are a popular choice for homeowners looking for the traditional appearance of sash windows without the ongoing maintenance associated with timber. The multi-chambered profile can provide strong thermal performance while resisting issues such as rot, warping and the need for regular repainting.
For period properties requiring a like-for-like visual replacement, uPVC can provide a practical balance between appearance, performance and cost. Woodgrain finishes and traditional sash detailing can also help the finished window complement the character of the property.
Aluminium Vertical Sliding Windows
Aluminium vertical sliders provide another option for homeowners who want the traditional sash silhouette with slimmer contemporary sightlines. Aluminium is naturally strong, allowing the frame to accommodate larger areas of glazing while maintaining rigidity.
The material is particularly suited to homeowners looking for a cleaner, more contemporary finish or larger openings where additional frame strength is beneficial. Aluminium vertical sliders can also be specified in a range of colours, allowing the traditional sash profile to work across both period and modern properties.
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Vertical Sliders Gallery
Take a look at some of our vertical slider installations. Click an image below to open the gallery.
Energy Efficiency and Glazing Options
Glazing plays an important role in the overall thermal performance of a vertical sliding window. Double or triple glazing can be specified depending on the required performance, while argon-filled units can help reduce heat transfer between the panes.
Modern vertical sliding windows can achieve strong Window Energy Ratings and low U-values when appropriately specified. The exact figures depend on the individual window and glazing combination, so product-specific performance information should be confirmed before publication.
Security Features for Vertical Sliding Windows
Modern vertical sliding windows are designed with security in mind, providing features that improve protection compared with many traditional timber sash systems. Internally beaded glazing places the glazing bead inside the property, helping prevent the glass from being removed externally.
Additional sash locking can secure the moving sections of the window at multiple points. This is particularly important on double-hung designs, where both the upper and lower sashes need to remain securely locked when the window is closed.
Start Your Vertical Sliding Window Project Today
With the style, materials, performance and finish considered, the next step is to find the right specification for your property. Whether you are replacing one sash window or upgrading multiple openings, a made-to-measure approach allows the design to be tailored to the size and character of your home. A free home survey provides the opportunity to assess the existing openings, discuss material and glazing options, and provide a quote based on your requirements. There is no need to guess what will work or what the project will cost before discussing your options.
FAQs
Are vertical sliding windows suitable for conservation areas and listed buildings?
Often, yes. Because uPVC and aluminium vertical sliders replicate the sash horns, deep bottom rails and Georgian bars of a traditional timber sash, they’re frequently accepted in conservation areas where a modern casement wouldn’t be. It’s always worth checking with your local authority, and we can advise on this at survey stage.
What’s the difference between a single-hung and double-hung vertical slider?
On a single-hung window, only the bottom sash moves while the top stays fixed. On a double-hung window, both the top and bottom sashes slide independently, which gives better ventilation control since warm air can escape from the top while cooler air is drawn in from the bottom.
What’s the difference between a vertical slider and secondary glazing?
A vertical slider replaces your existing window entirely. Secondary glazing is fitted alongside your existing window rather than replacing it, adding an extra layer of insulation and noise reduction while the original frame stays in place, which is often the right approach for listed properties.
Can vertical sliding windows be cleaned from inside?
Yes. Most vertical sliders include a tilt facility, allowing both sashes to tilt inward so you can clean the outside glass safely from inside the room, including on upper floors where cleaning from outside isn’t practical.
Are uPVC vertical sliders as secure as timber ones?
More so. Every uPVC and aluminium vertical slider we install uses internally beaded glazing, so the glass can’t be removed from outside, along with quality hinges and central and corner sash locking, giving a level of security original timber sashes were never built with.
How much do vertical sliding windows cost?
Vertical sliding windows typically cost £500 to £1,400 per window supplied and installed, depending on size, material and glazing. uPVC options are generally more affordable, while aluminium and bespoke heritage designs can cost more.
Do vertical sliding windows need much maintenance?
No. Unlike timber sash windows, uPVC and aluminium vertical sliders won’t stick, rot, warp or need repainting. Basic cleaning is all that’s needed to keep them performing and looking good for decades.