Secondary Glazing

Period homes, those which have been Listed or based in Conservation areas, often have ornate original windows, which are either kept as a feature or have to be retained under the Listing.

Guidance on Listed Building Consent

More Information from Selectaglaze

Although aesthetically pleasing, they are often draughty, allow noise in and can be seen as vulnerable points of the building. In all these cases secondary glazing can be a sound alternative to window replacement. It is a fully independent internal window, fitted on the room side of the existing primary window. It keeps the warmth in, dramatically reduces sound levels, retains the character of the original windows and as a reversible adaptation, is acceptable to both Heritage bodies and Conservation Officers.


Selectaglaze secondary glazing systems incorporate efficient seals to almost eliminate draughts and when glazed with low emissivity glass will reduce heat loss by up to 65%. This lowers running costs, improves comfort levels throughout the room and assists with carbon reduction objectives.


Bespoke and well fitted secondary glazing offers effective noise insulation. The secondary window frame is generally fitted 100-150mm away from the primary window, with the cavity working to limit noise transmission across the panes. Systems fitted in this way are capable of reducing noise levels by 42-45dB and even higher levels if a heavier glass is chosen.


Windows are normally seen as “soft targets” for intruders and a secondary window, especially when fitted with a simple lock and strengthened glass, provides an additional barrier to entry. Selectaglaze also offers enhanced systems accredited to Secured by Design and are a Police Preferred Specification.