Tracking: Not Defined

Sapphire Celebration Event- RSVP to our Open Event on the 21st, 22nd 23rd of June here.

Find Out More >

Increasing Energy Efficiency in Historic Buildings

This article was published on April 22, 2024

While historic buildings are beautiful, a frequent issue that homeowners experience is that these properties are often energy inefficient, and are not very draft-resistant, due to the dated technology installed in the home.

A large concern that homeowners of listed properties have is that you cannot elevate or improve your property in fear it will take away from its original aesthetics. However, despite these concerns, there are plenty of options available to you to increase the thermal efficiency of your home, without sacrificing its kerb appeal!

This article explores the different avenues you can explore to ensure your period property has the up-to-date energy efficiency measures.

Secondary Glazing

Similar to double glazing, secondary glazing is the process of installing another glass layer behind an existing glazed window, which helps to keep the heat in, and the cold out. This is a popular method of increasing thermal efficiency in listed buildings, as you do not need planning permission for secondary glazing.

Improve the performance of your existing sash windows with our bespoke secondary glazing services. In Grade I and Grade II buildings, including buildings where changes to windows are not possible, our secondary glazing can reduce heat loss by up to 65%, significantly reducing heating bills, whilst retaining the beauty of the building.

Available in 6 different styles, our secondary glazing units are custom manufactured to your requirements, designed for easy cleaning in over 200 RAL colours. Secondary glazing can be installed discreetly on the inside of window frames, designed to keep your home thermally efficient through conserving warmth in the winter and keeping cool in the summer.

Check out our Secondary Glazing here.

Vacuum Glazing

Vacuum glazing, which can either be installed into new windows, or integrated into existing windows for period properties, is also very similar to secondary glazing. However, instead of containing gas in the cavity between both window panes, there is a vacuum, which is actually more effective when it comes to thermal insulation.

Using advanced technology, vacuum glazing offers improved thermal and acoustic insulation for homes, revolutionising energy-efficient living, cutting down on energy bills and contributing to a greener future. Not only can our vacuum glazing be installed into new framed timber windows, but integrated into period properties through our restoration process, resulting in the retention of their vintage charm and aesthetics whilst upgrading to modern technology.

Despite being as thin as a single pane of glass, our vacuum glazing is nearly twice as thermally efficient as triple glazing, maintaining a more comfortable temperature inside the building, with a smaller reliance on heating or cooling systems. See below the benefits of vacuum glazing:

  • More Efficient Than Triple Glazing 
  • 15 Year Guarantee
  • Increased Noise Reduction
  • Thinner Than Double Glazed Units
  • Recyclable
  • Reduced ‘Double Reflection’ From Glass
  • Favoured Within Heritage and Conservation Situations.

Click here for more information on our Vacuum Glazing.

Sash Window Repairs

For heritage buildings, windows carry character that cannot be replaced, our window sash repairs are a cost-effective restoration option to retain their elegance. At ERW, our extensive experience of working on listed buildings means we can ensure your building has windows with the latest energy-efficiency and performance features, with no detriment to its appearance.

With our sash window repairs, we offer a range of services depending on the needs of the building, listed below:

  • Rotten Timber Removal and Repair – If your listed property has decayed or damaged timber in the window sashes, we can replace this with custom moulded timber, ensuring long-lasting performance and strength against rotting and cracking.
  • Full Draught-proofing of Windows – Through our Draught Seal System, parting and staff beads are replaced with new beads, including our brush seal. This  effectively succeeds in making windows draught-proof, while  preventing dust ingress and rattles caused by air gaps, as well as improving the thermal efficiency of the property.
  • Security Upgrades – Window security helps ensure the safety of a property. Our traditional-styled ironmongery protects against intruders, misuse, and accidents.
  • Hardware Upgrades – While maintaining appearance, we can replace or install all existing hardware. We can replace cords, improve sashes or pulleys, and cut brass sash lifts and catches, all whilst ensuring the window’s visual aesthetics are maintained.
  • Encapsulation and Replication of Original Leaded Units – We can replicate the aesthetics of your leaded windows to their finest detail, enhancing performance, longevity, and keeping visual appeal.

For more information, click here.

Window and Door Replacement

In the unfortunate case that your listed building has sustained irreparable damage to its doors or windows, our bespoke selections are bound to find the perfect replacement for you, with the option to replicate the existing door, with modern performance enhancements, such as thermal efficiency, high-performance locks, and more.

Our premium Wooden Doors are manufactured using the finest European Redwood, in over 150 colours. As thermally-efficient as they are durable, our wooden doors are highly customisable, replicating the aesthetic of your previous door.

Crafted from premium-quality timber, our Wooden Windows can be the best replacement for your historic property, with fantastic insulation, and a reduction in carbon footprint. We can ensure the vintage aesthetic of your windows are maintained, carefully crafted to your specifications.

For window and door replacement on a listed property, you will need planning permission. Do not worry, ERW has you covered, we deal with your local authority to ensure this is in place for you.


There are plenty of options to choose from when looking to improve the thermal efficiency of your historic property, without compromising the vintage appeal of the building, or changing its appearance at all!

Whether it’s improving the quality of existing windows, or searching for a replacement window (or door), we’re here to make sure that your demands are met, and that your building is equipped with thermal efficiency, built to last. 

If you’d like to book an appointment with us, please call 01642 456167 or email, and a member of our team will be in touch.

We also have a digital brochure available for inspiration. You can request a copy here.


Brochure Download

Click here to request a brochure and we will email one directly to your inbox.


Would you like one of our brochures?

Download Now

Other posts you might like

Recent Testimonials

Brochure Download