Can You Double Glaze Sash Windows? Discover the Benefits

Can You Double Glaze Sash Windows?

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Sash windows, with their classic charm and elegant aesthetics, are a beloved feature in many traditional British homes. However, one common drawback of these period windows is their single glazing, which can lead to poor insulation and higher energy costs. The question arises: can you double glaze sash windows to retain their charm while enhancing their efficiency? The answer is a resounding yes.

Double Glazing for Sash Windows

Double glazing involves a window featuring a unit with two panes of glass separated by a gap, usually filled with air or inert gas. For sash windows, this process can be more complex due to their unique sliding mechanism which naturally increases the depth of the overall frame compared to a side-hung casement window. Thick double or even triple glazing would increase the thickness of the sash window and make it look out of place in a period property. However, with advancements in window technology, it is entirely feasible to fit thin double glazing in sash windows without compromising their appearance or functionality. At Quickslide we use a 24mm double glazed unit instead of the standard 28mm unit commonly used for windows and doors to avoid bulky frames that protrude into the room.

Single Glazed Sash Windows

Single glazed sash windows have long been a hallmark of traditional British architecture, adorning the facades of Georgian, Victorian, and Edwardian homes. These windows, characterised by their elegant design and smooth sliding mechanism, evoke a sense of history and charm that is hard to replicate. However, while they offer significant aesthetic appeal, single glazed sash windows also come with certain drawbacks, particularly regarding energy efficiency and insulation.

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Converting Single Glazed Sash Windows

Many older homes feature single glazed sash windows, which, while aesthetically pleasing, offer minimal thermal efficiency. Converting these to double glazed frames can significantly reduce heat loss and improve sound insulation. The conversion process typically involves either secondary glazing or installing new, double glazed sash windows designed to replicate the traditional look.

Classic British sash windows retrofitted with double glazing for improved thermal performance and sound insulation.

Replacement Double Glazed Sash Windows

Replacement double glazed sash windows are often the best solution, as old timber frames can also be replaced with more energy efficient uPVC. Quickslide’s windows are designed to replicate the appearance of traditional sash windows but are fabricated using multi-chambered profiles and double glazing. They can provide benefits of improved energy efficiency as well as levels of noise reduction while maintaining the character of the property.

Here at Quickslide, we’re committed to offering a product that looks the part without losing any of the modern benefits of uPVC.

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Benefits of Double Glazed Sash and Case Windows

  • Enhanced Thermal Insulation
  • Superior Sound Insulation
  • Energy Efficiency with Low-E Coating
  • Increased Property Value
  • Improved Comfort
  • Reduced Condensation
  • Enhanced Security

Double glazed sash and case windows offer numerous advantages over their single glazed counterparts. The primary benefit is enhanced thermal insulation, which helps keep homes warmer in the winter, thus potentially reducing energy bills. Additionally, double glazing can even provide superior sound insulation, a significant advantage for properties in noisy urban areas.

Also, modern double glazed glass units often come with a low-emissivity (low-E) coating, which further enhances their energy efficiency by reflecting heat back into the room. This can make double glazed sash and case windows an attractive investment for homeowners looking to improve their property’s comfort and value.

Balancing Heritage and Efficiency

Quickslide has meticulously designed their sash windows to preserve the authentic look and feel of traditional sash windows. Whether you own a Georgian, Victorian, or Edwardian home, Quickslide’s sash windows can seamlessly integrate into your property, enhancing its historical charm. While heritage features are crucial, our sash windows are equally celebrated for their modern energy efficiency. Our sash windows incorporate cutting-edge technologies that can provide superior thermal performance and help reduce energy bills.

We’ve recently launched a 1.2 U-value upgrade for our sliding sash windows, something that just wouldn’t be possible with old fashioned single glazing!

To achieve a U-value of 1.2 for our sash windows, we are implementing several key upgrades.

  • We’re replacing some of the steel reinforcement in the sashes with plastic, which is a better insulator than steel.
  • We’re also incorporating more insulating materials into the window frame and cill.
  • The final touch is upgrading the coating on the glass unit, reducing heat loss by reflecting heat back into the room.

Together, these changes will hugely improve the thermal performance of our sash windows, ensuring they achieve a U-value of 1.2 W/m²K.

Further Reading:

What is a Horn on a Sash Window?

Paige Pipe

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Please note, our news articles are relevant and accurate at the time of release, but as technical developments dictate, and times goes by the information in this article may no longer be applicable. If you have questions, please contact us using our online contact form or call us on 03332 412 240.

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