Upgrading sash windows: Is double glazing the right choice?

If you’re living in a period property with original wooden sash windows, you know just how much charm and character they bring. But those beautiful old windows can sometimes let in draughts, noise and cold air – especially if they’re still single glazed.

Many homeowners wonder if replacing sash windows with double glazing is the best way forward, or if it might compromise the heritage look they love.

Here at Bereco, we’ve helped countless homeowners navigate this decision, blending modern energy efficiency with respect for original joinery and listed building regulations.

Let’s walk through your options and show you how upgrading your sash windows can make a real difference to comfort and energy bills – without losing that more traditional feel.

Why consider replacing sash windows with double glazing?

Old sash windows are often single glazed, which means just one pane of glass sits in each box frame. While this maintains the original look, it also means your home loses heat, suffers from noise pollution and can get uncomfortably chilly in winter. Modern double glazing, with two panes of glass separated by an insulating layer, offers a great way to boost thermal performance and make your home more comfortable year-round.

Upgrading to double glazed sash windows can reduce heat loss by up to 65% compared to single glazing, helping you keep your home warmer in winter and cooler in summer. This improves living comfort while cutting down on energy bills – sometimes by hundreds of pounds each year.

How does double glazing protect your period property?

One of the main concerns for owners of period properties is preserving the original look and feel of their homes. Modern double glazing can be fitted into new sash window frames that closely mimic the style and proportions of original wooden sash windows. At Bereco, we use sustainably sourced timber and advanced coating systems to ensure our new sashes blend seamlessly with your home’s heritage features.

Our double glazed timber sash windows exceed the latest building regulations and can achieve impressive U-values – starting from 1.3 W/m²K, which is 7% better than current guidelines. This means you get all the benefits of modern energy efficiency without sacrificing the charm of your original sash.

What are the costs and benefits of upgrading?

Upgrading from single glazing to double glazing does involve an initial investment. Double glazed sash window costs can vary depending on the size, style and complexity of your project, but the long-term savings on energy bills and increased property value often make it worthwhile.

Here’s a quick comparison:

Feature	Single glazing	Double glazing
Heat retention	Low	High
Noise reduction	Minimal	Significant
Energy bills	Higher	Lower
Maintenance	More frequent	Less frequent
Property value	Lower	Higher

Is double glazing suitable for listed buildings and conservation areas?

Many homeowners worry that replacing sash windows with double glazing isn’t allowed in listed buildings or conservation areas. While it’s true that some properties have strict conservation rules, there are often ways to upgrade your windows without compromising on authenticity.

Conservation guidelines vary from area to area. In some locations, standard double glazing may be permitted, while in others, planning authorities may require more sensitive solutions. That’s why it’s so important to check with your local council and, where needed, gain approval before making any changes.

At Bereco, we work closely with conservation officers and homeowners to ensure our solutions meet both heritage and modern energy standards. Our Heritage Range is specifically designed with these properties in mind. Featuring slimline double glazing and traditional mouldings, this range offers a sympathetic solution for listed homes and those in conservation areas. The frames replicate the fine sections and detailing of original period joinery, while discreetly incorporating modern double glazing. The result is a window that preserves the historic appearance of your home while significantly improving energy efficiency and comfort.

How does double glazing affect noise reduction and heat retention?

Double glazing is a proven way to reduce noise pollution from busy streets, making your home quieter and more peaceful. The extra pane of glass and the insulating layer between them act as a barrier to sound, as well as heat.

Heat retention is another major benefit. Double glazed sash windows help keep your home at a more stable temperature, reducing cold spots and draughts. This improved thermal efficiency means your heating system doesn’t have to work as hard, saving you money on energy bills.

How can Bereco help?

At Bereco, we’re sash window experts with years of experience in crafting high-performance timber sash windows for period properties. We use only sustainably sourced timber and the most advanced coating systems, ensuring our new sashes are both beautiful and built to last.

Whether you need new sash windows, replacement sash windows or advice on upgrading your existing sash windows, our friendly team is here to help. We’ll guide you through every step, from choosing the right style and glazing to ensuring your project complies with all relevant building regulations.

Ready to take the next step with your sash windows? Get in touch with our friendly team to discuss your project and discover how we can help you upgrade your home’s windows for better comfort, lower energy bills and a more beautiful period property.