If you own a listed building, there is a high chance that you are the victim of much envy! Listed buildings are so sought after, and they are the subject to a lot of architectural respect. Therefore there is a Listed Building Consent process – to maintain the aesthetic integrity of the property’s era. However, when you are wanting to conduct some home improvement projects, this can be frustrating. Now more than ever, people are making changes to their homes to ensure they are more energy efficient, and one way to do this is to improve the thermal efficiency of their windows. So, for a partial or full sash window replacement, what is the Listed Building Consent process?

What changes to my windows may require Listed Building Consent?

Any home improvement that makes a change to the external fabric of the listed property will need consent from the local authority. There are four main options you have when you are looking to optimise your windows for greater energy efficiency. Some of the options are more likely to be approved through the Listed Building Consent process, whereas others are slightly trickier but will offer your listed home more benefits in terms of energy efficiency.

Draught sealing and overhauling

This is the option to increase your windows’ energy efficiency without the expense or process of replacing the windows entirely. During a draught reseal and overhaul, the sashes are removed and planed, and rehung on a new nylon plaited sash cord. They are correctly balanced and can provide more insulation by keeping out draughts. This option is not required to go through the Listed Building Consent process.

Full or part replacement with single glazing

Single glazing is often found in listed buildings, and although they look beautiful, they do not offer as much heat retention for your property. The replacement of these with new single glazing windows could have influence, as a draught resealing is included in the service. The new windows will have the inclusion of internal glazing bars, which is often demanded by Conservation Officers. This is the most likely option to be approved by the Listed Building Consent process, and the most inexpensive of the replacement options.

Full or part replacement with slim double glazing

Replacing your single glazing, original windows, with slim double glazing will definitely make a difference to the warmth of your home. During this process, 22mm glazing bars are used, and at times it is requested by Conservation Officers for them to be no more than 20mm. Although there is a chance that an application for a sash window replacement using double glazing may be denied, it is always worth applying as it is also dependent on the state of your current windows and your architectural surroundings.

Full or part replacement with Fineo glazing

Fineo glass is the most energy efficient glass that you could benefit from in your listed building. As an incredibly thin glass with a U value of 0.7, as opposed to single glazing having a U value of 5.8, this glass is incredibly insulating. It will dramatically improve the energy efficiency of your home. This option is the least likely to be approved through the Listed Building Consent process, but it is not impossible. It’s important to strive for this option!

What is the process of applying for Listed Building Consent?

You may be wondering what the process is to apply for Listed Building Consent. With Wandsworth Sash Windows, our team oversees the entire thing. This saves you from having to worry about the process, as it can take a while (at least 12 weeks from the point that you contact us, and often longer). The process that we will go through initially consists of:

  • Inspecting and measuring your existing windows
  • Producing technical drawings of our plans
  • Producing a report on the condition of your existing listed building windows
  • Drawing elevations of the entire listed property
  • Creating a Heritage Statement regarding the history of the property and its notable architecture
  • Pinpoint the location and provide block plans
  • Consulting with the council to provide updates on the application

At Wandsworth Sash Windows, we have a resolute team to handle the application for Listed Building Consent. This allows it to be a seamless process, and once the application is approved our team will provide you with windows of an exemplary standard. If you have any questions about Listed Building Consent, you can get in touch with our experts for more information.

Contact the Wandsworth Sash Windows team

Talk to us – we can help with your bespoke window, door and joinery requirements. Call 02079247303 or email