Previously, we have looked into permissions to convert a house into flats (subdivision). The opposite of this is amalgamation, where you convert flats into a single house.
Image above – extension by Ben, architectural designer from Lambeth, London. See more and shortlist his practice for your home project.
Do you need planning permission to convert flats into a single house?
Unfortunately, the rules on this aren’t very clear and will ultimately depend on your local authority and your proposal.
Planning permission is not usually required for internal works, where there is no material change of use.
The Town and Country Planning Act 1990 is clear that sub-dividing a house into flats constitutes a material change of use. However, this national legislation is not as clear regarding the amalgamation of flats into a single house.
This has led to some local authorities setting their own policy, particularly in relation to housing stock needs for the area. So your first check should be your local authority’s planning policy. A local architect who has dealt with similar applications will be able to help you navigate this.
De-conversion and planning permission
This is where the original single dwelling, at some point in the past, was converted into flats. De-conversion is the term used when re-instating the house back to a single dwelling.
Check the records
Before you do anything else, it’s worth checking to see what the official status of your properties is. It’s possible that planning permission was never gained for subdividing the original house. Therefore, in planning terms, your property would still be deemed as one property. In this case, it’s unlikely that planning permission would be needed.
However, you will still need building control approval for any work you do, regardless of the planning status (see below).
Certificate of Lawful Development
Where planning permission is not required, it’s usually a sensible idea to get a Certificate of Lawful Development for a conversion like this.
This will become very important when you come to sell or get a mortgage on your house.
Conservation Area Consent and Listed Building Consent
If the house is in a conservation area, you may need conservation area consent if any demolition works are required as part of the development. Likewise, you will need listed building consent if your property is listed.
Property conversions will require Building Control approval, regardless of the planning requirements.
Party wall award
If you are doing work that affects the structure of a shared wall or floor with a neighbouring property, you will need a Party Wall Award. See our article here on whether you will need a party wall surveyor: https://designfor-me.com/advice-and-tips/do-i-need-a-party-wall-surveyor/
Finding the right architect for your conversion
Design for Me is a free platform to help you quickly find the right design professional for your home project. My name is Emily Barnes and as a residential architect myself, I started Design for Me after finding that talented and innovative smaller firms and individuals, who are perfectly placed to design new homes, extensions and renovations, can often get buried under the online profiles of large commercial companies.
Before Design for Me, the right architect was very difficult to find!
Once you register your project, we’ll match it with 100s of top architects in your area and beyond, and you can see who may be available and eager to work on your project straight away.
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