Secondary Glazing - Publications
Secondary Glazing Publications

The Energy Performance of Old Windows

Europe can be proud of the large number of historic buildings across its countries. But these buildings gobble up large amounts of energy. Old window are ‘weak points’ from a building energetic point of view, have a high thermal transmittance value (Uvalue), are not airtight, are prone to condensation, cause discomfort in users positioned near the window can lead to overheating.


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Secondary Glazing Publications

Energy Efficiency and historic buildings

English Heritage supports the Government’s aims to improve the energy efficiency of existing buildings through Part L of the Building Regulations. Many improvements can be carried out, often at a relatively low cost, significantly enhancing the comfort of the building for its users, as well as providing savings on fuel bills. Such improvements can also help in meeting the Government’s greenhouse gas emission reduction targets.

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Secondary Glazing Publications

What are the benefits of secondary glazing?

Secondary glazing is a cost effective way of improving heat retention and sound reduction in your home, as well as providing some additional security. It can be a great less expensive alternative to replacing double or triple glazed primary windows. Secondary windows units usually have separate handles and open so that you can get access to clean and open your primary windows.

Secondary Glazing Publications

Secondary glazing can result in significant cost savings

Secondary glazing is considerably cheaper and easier to fit than replacement windows because it doesn’t require complete removal and replacement of your existing windows.

Secondary Glazing Publications

Heat loss is reduced with secondary glazing

A major long-term benefit of secondary glazing is the heat retention properties. This is because it adds a second layer of glass behind your existing primary windows that reduces both the amount of warm air that can escape from your home and the amount of cold air that can enter.

Secondary Glazing Publications

Experience less external noise with secondary glazing

Secondary glazing also acts as an extra physical barrier against outside noise, reducing the amount of sound coming into your home through (closed) windows. This noise reduction can be further improved by installing special sound-reducing laminate glass, or by having a gap of at least 100 mm between the secondary and primary window and lining the window head and reveals in between with acoustic tiles.

Secondary Glazing Publications

Sliding secondary glazing

Sliding secondary glazing units are removable and hence easier to clean than fixed units. Horizontally sliding secondary glazing units are perfect for windows and doors with vertical bars while vertical sliding ones are an ideal fit for windows with horizontal bars..

Secondary Glazing Publications

Fixed secondary glazing

English Heritage supports the Government’s aims to improve the energy efficiency of existing buildings through Part L of the Building Regulations. Many improvements can be carried out, often at a relatively low cost, significantly enhancing the comfort of the building for its users, as well as providing savings on fuel bills. Such improvements can also help in meeting the Government’s greenhouse gas emission reduction targets.

Secondary Glazing Publications

Lift-out secondary glazing

Like magnetic and sliding secondary glazed units, lift-out units can, as the name suggests, be lifted out. However, they’re not recommended for areas where regular access is required.

Secondary Glazing Publications

Energy Efficiency and historic buildings

English Heritage supports the Government’s aims to improve the energy efficiency of existing buildings through Part L of the Building Regulations. Many improvements can be carried out, often at a relatively low cost, significantly enhancing the comfort of the building for its users, as well as providing savings on fuel bills. Such improvements can also help in meeting the Government’s greenhouse gas emission reduction targets.