Before you start building, check what your property allows
Planning an extension often begins with deciding how much space you need and where the additional room should go. But before finalising the design or booking construction work, you need to establish whether planning permission is required.
Some home extensions may fall under permitted development rights. These allow certain works to proceed without a full planning application, provided specific conditions and limits are met. Not every property or proposed extension qualifies.
The rules can depend on the size, height and position of the extension, the property’s planning history and whether special restrictions apply. Building regulations are a separate consideration and may still apply even where planning permission is not needed.
What should you check first?
Before proceeding with your proposed extension, check the following:
- Property restrictions: Is your home listed, in a conservation area or subject to other planning controls?
- Extension dimensions: What are the proposed height, depth and position relative to the existing house and boundaries?
- Previous alterations: Have earlier extensions or changes affected the available permitted development rights?
- Building regulations: Will the work need approval for structural safety, insulation, fire safety or other relevant requirements?
How to check the requirements step by step
- Prepare an outline of the proposal: Record the intended layout, dimensions and position of the extension.
- Review official guidance: Read the GOV.UK guidance on permitted development rights for householders.
- Contact your local planning authority: Check whether local restrictions or property-specific conditions affect your proposal.
- Arrange the necessary approvals: Confirm the planning position and building regulations requirements before the relevant work begins.
Planning permission and building regulations are different
Planning permission concerns whether a proposed development is acceptable in planning terms. Building regulations set requirements for aspects of construction, such as structural safety, energy efficiency and fire safety.
A project may need one, both or, in some circumstances, neither. The answer depends on the proposed work and the property, so don’t assume that satisfying one requirement automatically satisfies the other.
New builds and structural work, managed from start to finish.
Key takeaway
Check the planning position and building regulations separately before committing to an extension design or construction date.
Common mistakes to avoid
- Assuming every single-storey extension qualifies as permitted development.
- Relying on a neighbour’s extension as proof that your own proposal will be allowed.
- Overlooking restrictions linked to a listed building or conservation area.
- Starting work before confirming which approvals and checks are required.
Where the requirements are unclear, seek advice from the local planning authority or a suitably qualified professional.
How Proactive Construction can help
Proactive Construction undertakes residential extensions, conversions and refurbishment projects. The team can discuss your proposed work and coordinate with the relevant design and building professionals as required. The planning position should be established before construction proceeds.
Explore Proactive Construction’s extensions, conversions and refurbishment services.
