Can I put double glazing into my listed property? This is a question we get asked on a daily basis.
Firstly what does a listing mean? Listing means the building is included on a national register as a property of architectural or historical importance. It means that its style and character must be maintained and owners have a responsibility and duty to ensure its upkeep.
When upgrading or refurbishing your windows most councils and conservation officers would ask that you renovate your windows where possible and economical, saving as much of the original window. Upgrading is nearly always preferable to replacement.
Might ‘Part L’ of the Building Regulations require me to replace an old timber window? Not with a historic building, "Historic" in the context of Part L includes buildings that are listed or in a conservation area. Whilst Part L seeks to improve the energy performance of all buildings, including existing ones when altered it states that with historic properties a reasonable approach must be taken that balances the conservation of fuel and power with the conservation of the fabric. Unlike replacement, window repair is not subject to Part L. Similar requirements apply in Scotland under Part J.
Most of our customers ask if we are able to put double glazed units into their existing windows (insert into the original glazing bars), unfortunately this isn’t something we like to do, the glazing bars where not designed to take the weight of double glazing and would eventually buckle. For double glazing to function correctly and efficiently it also needs to be of a certain width, therefore our double glazing wouldn’t fit into and sit flush on an existing glazing bar.
There is no quick answer to this question as each property is assessed on a case by case basis by your local conservation officer prior to any work, you will normally be asked to apply for listed building consent or planning permission for your planned window works.
For more help and information on your listed property and double glazing go to www.spab.org.uk (the society for protection of ancient buildings) or www.lpoc.co.uk/ (the listed property owners club).
To find your local council visit www.gov.uk/find-your-local-council