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The Definitive Guide to Sliding Sash Windows: Classic Charm Meets Modern Performance
The Definitive Guide to Sliding Sash Windows: Classic Charm Meets Modern Performance
Classic charm: KJM installations bring period properties back to life.
Key Takeaways
- Classic Design, Modern Tech: Modern uPVC versions replace draughty original timber with A-rated thermal efficiency and security.
- Innovative Mechanisms: Traditional heavy weights are replaced by hidden spiral spring balances for smooth, reliable operation.
- Roseview Excellence: KJM offers three distinct tiers (Ultimate, Heritage, and Charisma) to suit conservation-grade or contemporary projects.
- Low Maintenance Living: These windows won’t rot or warp and feature a clever tilt function for easy cleaning from the inside.
There are few architectural features as instantly recognisable as the sliding sash window. They are the defining characteristic of Georgian elegance, Victorian industry, and Edwardian style.
If you own a period property, maintaining its character is paramount. Yet, original timber sash windows are notorious for rattling, draughts, and requiring endless maintenance. At KJM Group, we believe you shouldn’t have to compromise between historical authenticity and modern comfort.
What Exactly is a Sliding Sash Window?
Unlike more common ‘casement’ windows hinged at the side, a sash window opens vertically. They consist of two framed panels, known as ‘sashes,’ which slide up and down within the frame. In most traditional designs, both the top and bottom sashes can slide, allowing for flexible ventilation.
A Brief History
The oldest surviving examples in England date back to the 1670s. Regardless of their origins, the sash window thrived in Britain, becoming the dominant style for nearly three centuries. Because they remain flush with the wall, they were the perfect choice for city centres and townhouses.
How Do Sash Windows Work?
Window glass is heavy. To allow a vertical window to slide smoothly and stay open at any height, the weight of the sash must be counter-balanced.
Traditional Weights & Pulleys: Historically, this was achieved using heavy lead or cast-iron weights hidden inside a box within the window frame, connected via a cord over a pulley.
Modern Spring Balances: Most modern uPVC versions use a sophisticated spiral spring balance. This allows for much slimmer, neater window frames and smooth, reliable lifting.
Introducing Roseview: The Pinnacle of Modern Sash Windows
KJM Group has partnered with Roseview Windows, the UK’s leading manufacturer of uPVC sliding sash windows. They meticulously engineer windows to replicate the charm of timber while providing A-rated energy efficiency and security.
1. The Ultimate Rose: Unparalleled Authenticity
Widely considered the best uPVC sash window on the market, the Ultimate Rose is frequently approved for use in conservation areas. It features an exceptionally slim 35mm mid-rail and mechanical joints that mimic handcrafted timber joinery.
2. The Heritage Rose: Period Charm
A superb choice for Georgian and Victorian properties, balancing authentic looks with modern performance. It features a 44mm mid-rail and offers excellent soundproofing—ideal for homes near busy roads.
3. The Charisma Rose: Contemporary Performance
Designed for modern projects or budget-conscious renovations where the style of a sash window is desired, featuring a 60mm mid-rail and welded corner details.
At a Glance Comparison
| Feature | Ultimate Rose | Heritage Rose | Charisma Rose |
|---|---|---|---|
| Best For: | Conservation & Premium | Period Properties | Modern & New Build |
| Mid-Rail: | 35mm (Ultra-Slim) | 44mm (Slim) | 60mm (Standard) |
| Corner Joint: | Mechanical (Timber look) | Welded | Welded |
| Security: | PAS24 / SBD capable | PAS24 / SBD capable | SBD capable |
The Importance of Details: Customising Your Window
A sash window is defined by its details. Roseview and KJM offer customisation from various glass types and gasket colours to high-quality furniture finishes like chrome, gold, or antique brass.
The ‘Run-Through’ Sash Horn
A critical Victorian detail is the ‘sash horn’—the decorative spur on the top sash. Roseview windows feature authentic run-through horns, sculpted integrally from the profile itself, just as they would be on a timber window.
DESIGN YOUR DREAM WINDOW
Ready to see how these windows look on your home? Use our interactive tool to experiment with colours and hardware.
Launch Visualizer ToolFrequently Asked Questions
Yes. They feature high-security cam locks, reinforced frames, and can be upgraded to PAS24 and Secured by Design standards.
Often, yes. The Ultimate Rose is specifically designed for this purpose, mimicking historical timber so accurately it is frequently accepted by conservation officers.
No. Modern uPVC versions are A-rated for energy efficiency, using high-quality double glazing and durable gaskets to eliminate draughts.
No. Most Roseview models include a ’tilt facility,’ allowing both sashes to tilt inwards so you can clean the outside glass from inside the room.
Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.
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