A ‘listed building’ is a building or structure that is of national importance due to its architectural or historic interest. It is included on a special register: the List of Buildings of Special Architectural or Historic Interest.

Any building with a special historic and architectural interest can be nationally designated as a ‘listed building’. It then becomes legally protected and it cannot be altered, extended or demolished without the express consent of the local planning authority.

View Architecture for London’s portfolio of recent projects, including listed buildings.

Is my building likely to be listed?

There are many listed buildings in the UK, and they form large parts of historic cities such as London.

Almost all buildings older than 1700 are listed due to their age and rarity, and most Georgian and early Victorian buildings are too (those built between 1700-1840). There are many later buildings also listed but it is less common, particularly for residential properties.

A building usually has to be at least 30 years old before it can be eligible for consideration.


In England, there are 374,081 listings on the national register. However many of these entries include multiple buildings and therefore the number of listed buildings is higher. Historic terraces, for example, are often listed collectively.

In total it is estimated that there are half a million buildings in England protected by being listed, which equates to around 2% of all buildings.

Due to the historic nature of London, it contains more than 5% England’s listed buildings. Most are in the older preserved parts of the city, in the London Boroughs of Westminster (3,982), Camden (1,946), Kensington and Chelsea (1,331), Islington (1,046), Lambeth (942), and Tower Hamlets (907).

A solicitor would usually identify if a building is listed when it is purchased, due to the additional legal obligations of ownership.

Which parts of a building are listed?

When a building is listed, it is listed in its entirety. This means that both the exterior and the interior are protected as well as the grounds of the property. Therefore any alteration, extension or demolition to the exterior, interior or grounds will require consent from the planning authority.

With old buildings, it is common for there to have been numerous extensions made over the years. Regardless of the age of the extensions, these too will be protected.


Although the whole property is listed, each floor and room will have varying levels of importance. An architect working with specialist consultants will be able to advise. They will guide the proposals and build a case for the development when seeking consent.

Usually, the original parts are of most interest and are the least likely to be possible to change. Old extensions are also likely to be considered significant, especially when they have been well built, or if they are unusual and therefore part of the history of the building.

It is usually more straightforward to achieve consent to alter modern extensions, or areas that have lost more of their historic character through unsympathetic historic development. The changes may still affect the relationship with the historic parts of the building and therefore still need to be considered carefully.

The process of removing poor quality alterations, and reinstating historic character is usually supported.


Subdividing rooms may be contentious even if this would have little impact on the historic fabric. The ground floor and first floor are typically considered as principal floors and the plan form is usually protected to a greater extent here. Often there is more flexibility to add new rooms and partitions to create, for example, a new bathroom on the lower ground floor, or at second floor.

Grades of listed buildings

Each listed building will be graded and this is stated in the listing. There are three grades as follows:

  • Grade I: These are the most protected and account for 2% of listed buildings. They are considered to be of exceptional interest. The local authority will consult with Historic England when they receive applications for listed building consent.
  • Grade II*: These are particularly important and account for 4% of listed buildings. The local authority has the discretion to involve Historic England for applications. This will usually depend on the scope of the works proposed.
  • Grade II: These are classed as having special interest and account for 94% of listed buildings. Applications for alteration works are usually dealt with by the conservation officer at the local authority. This listing is most likely for residential dwellings.
  • Locally Listed Buildings:
    Sometimes the local planning authority will locally list a building. These are not statutorily listed and therefore this creates no additional planning controls. Consequently, locally listed buildings do not require listed building consent and therefore only planning consent will be required when applicable. If planning consent is required, the planning authority will treat the building as a heritage asset. This will be a consideration when determining a planning application.

Carrying out repairs

Where parts of the building are of poor quality consent is still required if wholesale replacement is desired. If the repairs are small these are usually acceptable without consent. However, it is important to understand that what you and the local authority consider being a “repair” may not be the same.

It is best to check any works with the local authority, an architect or a specialist consultant. For example, replacing a whole window would require consent but replacing a section of timber or a single piece of glass usually would not.

Repairs should also be made like for like and use traditional methods that match the surrounding areas. This is not just to satisfy heritage conservation but also for technical reasons. Inappropriate modern materials such as cement-based plasters and oil-based paints can trap moisture in solid walls and cause problems such as damp, or simply crack where they meet historic fabric.

It is advisable to use architects, contractors and builders who have experience working with listed buildings who can advise on the appropriate works.


Inappropriate modern repairs can also impact the aesthetic appearance of a building. Glass is a typical example which is often overlooked, and repairs should match adjacent panes.

Many Georgian and Victorian buildings still have their mouth-blown or hand-drawn glass, these refract light and give a wavy character. This gives warmth and softness to light entering windows. In contrast, 20th Century glass is usually machine-drawn or float glass which is flatter and has less character.

Whilst changes to glazing may sound minimal, once carried out they can have a drastic impact on a listed building and might not be considered an acceptable repair.

Consent to alter or extend a listed building

If the proposed works are more significant than repairs then consent will be required. To acquire consent to alter, extend or demolish a listed building an application must be made to the local planning authority. This is a similar process to planning consent but requires a separate application.

Listed building controls are in addition to any planning regulations that apply. The applications are made at the same time and would usually both be submitted by the Architect. With listed buildings, considerably more information will be required.

If the works are only to the interior of a listed building then planning consent might not be required. In this case, just listed building consent will be necessary. Drawings will still need to be prepared by an architect and submitted to support the application.

For applications for listed building consent, a conservation officer will be appointed by the Local Planning Authority to asses the proposals, and this would be in addition to a planning officer when planning consent is also applied for.

We always recommend a pre-application meeting with the local authority’s conservation officer to present the proposals and to discuss any alternative approaches if required.


The success of an application often relies on the balance between the careful refurbishment of period details and any new alterations required.

Architecture for London has significant experience working with historic buildings and are aware of the specific issues involved, particularly with the extension and refurbishment of grade II listed Georgian and Victorian houses. We can advise on design proposals and early stage in projects to develop an overall strategy. We also work closely with specialist heritage consultants when working on listed buildings.

Please visit the Architecture for London projects page to view our previously completed listed buildings.