Secondary Glazing for Listed Buildings

When a building has been listed it is protected by law and Listed Building Consent might need to be obtained before any changes are made to it. Repairs that match exactly may not need consent, but examples of work, which may do include changing (or adding) windows and doors, as the effect of any repairs is not always straightforward.

The owner of a listed building carries the responsibility of applying to their local authority for Listed Building Consent. The first step should be to ask the authority’s Conservation Officer if your proposals are likely to be accepted before making a formal application, saving you the time and money of an unsuccessful application. Your local authority will give you the appropriate form for making your application.

Usually, you will be required to replace ‘like with like’ in all aspects – materials, construction and finishing – although you may be allowed to upgrade the specification to include insulated sealed glass units and draught proofing, subject to respecting the character of the building and taking proper account of the original case for the preservation order.

Local authorities have control of applications for Listed Building Consent and over minor changes, but have to notify English Heritage when they first receive applications affecting buildings of outstanding national interest (normally those listed Grade I or II). English Heritage advises local planning authorities and the Secretary of State for the Environment, Transport and the Regions on the most important applications.* Local authorities may refuse any Listed Building Consent, but subject to local variations, can grant consent for works to Grade III listed buildings.**

You will usually have to wait 6-8 weeks for a decision on your application. If consent is refused, you have six months to appeal to the Department of the Environment, Transport and the Regions.

*Since 1993, agreements have been made between English Heritage and a number of London boroughs, delegating responsibilities to them for dealing with proposals for minor alterations to Grade II listed buildings.

**In Greater London, English Heritage has additional powers, inherited from the former Greater London Council, to direct the decisions of boroughs on all Listed Building Consent applications.

English Heritage can be contacted at

To contact your local authority visit

Conservation Areas

When a property is located within a designated Conservation Area (covered by an Article 4 Direction) then Conservation Area planning permission might need to be obtained before secondary glazing is installed.

Although the regulations allow for the use of any suitable material (e.g. wood, metal or upvc), in practical terms this is not the case. The considerations here are aesthetic and most modern materials cannot comply with the requirements to match as exactly as possible the dimensions, features and decorative mouldings etc. of the original. You may not need to replace ‘like with like’ where the windows cannot be seen from a public thoroughfare, but you will need to discuss this with your local authority before submitting your application. Your local authority will usually be able to send you a design guide for your area as well as giving you the appropriate form for making your application.

To contact your local authority visit


Please note that the information above is by no means comprehensive and is intended to provide only initial guidance for occupiers of Listed Buildings or properties within a Conservation Area. Should you require any further assistance, please feel free to contact one of our team members.