Can I Build An Extension On My Listed Building?

16/12/2022

Listed buildings are something of a speciality of ours. We have over 25 years of experience working on old buildings, and we know it’s a process that takes skill with documentation and administration, as well as construction and building expertise. Luckily, we’ve got lots of know-how with both! The answer to ‘Can I Build An Extension On My Listed Building’ is… maybe!

While you always need express permissions from the Local Planning Authority to undertake any construction or renovation projects on a Listed Building, you’d be surprised about the flexibility that you can have within the LPA’s stipulations and permissions. If you want to know how to find your Local Planning Authority contact address, type your postcode into this LPA website. (For much of Cornwall, this will be Cornwall Council; find its Planning Portal here.)

You will also need to apply for Listed Building Consent if you want to build an external structure, such as a conservatory or extension of external walls etc. This is an application form you can also get from Cornwall Council; find out more about the application for Listed Building Consent in Cornwall here.

Are Extensions Allowed On Listed Buildings?

There is some guidance on this from National Heritage; if the renovations or extensions are deemed ‘useful’ and ‘viable’, extensions and renovations can be considered. When you make your proposal for the extension you want to make, you must show that you understand what these changes will do to your building, and to the area around it. For example, if you are adding a glass conservatory to a granite cottage, do you understand what this will do to the stonework, and to the temperature of those exterior walls, and how will its use as a conservatory affect the masonry and any pointing etc? At this stage of writing your proposal, it’s a good idea to get a constructionist or builder to look over and give you some advice on the planning permission proposal, as an experienced builder will understand the true effect of the building work or extension.

What Documents Should I Submit To Cornwall Council To Get Permission To Extend My Listed Building?

Any Local Planning Authority will require the following documentation, which should all be submitted in one go, at one time:

An official form for requesting listed building permission (available from your LPA)
A diagram and plans of the building or structure as it is now on the plan
Plans and diagram for the intended addition or modification to the building
Details of planned works’ concepts and design principles
Heritage Impact Evaluation
Other important documents or those that the LPA requests (your individual LPA will have details on their websites to inform you of any additional documentation)
Design and Access Statement, which will detail the history of works on the house or Listed Building so far, and a more detailed description of the particular features of your Listed Building (e.g. masonry, slates, door, windows, fireplaces, chimneys, particular slates- such as Delabole or rag slate– staircases, flooring, etc)
In your Design and Access Statement, there is also an expectation that you will discuss the project management of your extension; this is where advice and guidance from your chosen construction team or building contractors will be vital. You must detail the process, who will be doing the extension work,(and why they are qualified to do the extension work), and the materials you will use (these may have to be ‘period-appropriate, such as using lime render, instead of concrete)

As you plan your extension on your Listed Building with your builder or construction team, you should ask them about the ‘permanence’ of any changes or modifications to your Listed Building. For example, if you’re adding an extension, could the extension be removed, if it really came down to it. A Local Planning Authority is more likely to say yes, if they feel that any risks can be reversed and mitigated for.

Got more questions about Listed Buildings? Read our other articles to find out more about maintenance, budgets and renovations:

Hysmark is with you every step of the way when it comes to renovating or building an extension on your Listed Building. We can help with paperwork and applications to your LPA, as well as bringing our decades of experience and expertise to the building work itself. Get in touch or ring 01288 381256 to begin the process today!