Reglazing windows with insulated glazing is a new trend for Listed buildings


    As energy costs continue to rise in the UK and Europe, many homeowners are looking for ways to improve the efficiency of their period and listed buildings and single-glazed windows in particular.

    One way to do this is by double-glazing listed building windows with insulated glazing. This is a new trend for period properties that is driven by recent client change challenges and glazing technology improvements.

    Retrofitting preserves classic features and improves the energy efficiency of windows and classic french doors.

    Special shape double glazed unit for the arch window section. 

    (Image source: chameleon windows restoration and decoration) 

    Insulated glazing evolved over the past years; same as smartphones, glazing has become thinner, and its insulation performance increased drastically.

    We’ll outline everything you need to know about reglazing old windows with modern insulated glazing, including the benefits and drawbacks of this approach.

    The technology gives new life to period wooden window

    First of all, let’s talk bout the technology which drives the trend behind the glazing retrofitting trend.

    Slimline double glazing

    Double glazing is not a new concept; it has been in the market since the 1980s, but at the time, the specs of such glazing did not satisfy conservation officers. The glazing units were too thick for retrofit single glazed sashes. The visible scaper was also an issue.

    Later the manufacturers managed to produce thinner options and called it slimline double glazing.

    However, some of the planning authorities still did not find these glazing options satisfactory enough to grant permission for reglazing.

    VIG – vacuum insulated glazing – Vacuum glazing

    The next thing for double-glazing listed buildings was a VIG glass. Pilkington Spacia was the first mass-market product, but it did not fit the retrofitting market because of its visible caps, which the manufacturer uses to remove the air to create a vacuum.

    The perfect double glazing for listed buildings

    Three years ago, the new double glazing hit the market. It was Panasonic, in partnership with AGC and its new brand of vacuum double glazing FINEO glass.

    This new VIG glazing brand fixed the issue of its predecessor by removing the cap from the glass surface. This improvement was reconsidered by conservation officers, and we see now that planning authorities are more in favour of giving planning permission for this double glazing.

    Reglazing old windows is a new trend for Grade 2 listed

    Sash windows restoration companies like Chameleon windows restoration and decoration,, now see the trend for listed building window reglazing services.

    Thanks to improvements in VIG glazing, homeowners now have a perfect solution which makes their windows more efficient as well as helps to preserve original joinery.

    It is more highly likely to get permission for reglazing windows with FINEO glass than for full window replacement with new double-glazed sash windows.

    Window insulation principles – a bit of the theory to understand why VIG is a brilliant glazing technology

    As you know, there are two ways to improve the efficiency of your period windows: insulation and draught-proofing. Let’s see how insulation works.

    Glass is an excellent heat conductor. When the sun hits it, the glass warms up and transfers the heat inside the building. The same happens when it’s cold outside and you turn on the heating. The heat goes through the glass and outside.

    The main window insulation principle is to create a barrier which stops the heat transfer through the single glass pane. In the case of secondary glazing, it basically adds the second line of “windows” and an air gap between secondary glazing and window which stops some of the heat loss. The first double-glazed united also has only air between the glass panes.

    Later inter gases were inflated into the gap between glass panes, which has lower heat conductivity than the air.

    As you might know from school, a vacuum almost does not transmit heat, making it an ideal insulation barrier for windows.

    To summarise the above

    We are all after the benefits which double glazing offers; reduced external noise levels and improved energy efficiency and security but living in a Listed building makes the whole process of double glazing windows not as easier, and the appearance of the property must not be intact.

    The property owners now have a perfect solution for reglazing their windows with vacuum glazing and preserving their window’s classic design.