House Extensions Planning Permission in Canterbury
Whether you need planning permission for house extensions in Canterbury depends on three things: your property's permitted development (PD) rights, whether your address sits inside a conservation area or Article 4 zone, and the size and position of what you're building.
Canterbury falls under CT1, CT2, CT3, CT4 — large parts of the historic core, particularly around Canterbury Cathedral (UNESCO), sit inside a conservation area where PD rights are restricted. We handle planning submissions to the local authority on every project we run here.
Most house extension projects in Canterbury either need full planning permission or qualify under PD with a lawful development certificate. We'll tell you which after a 30-minute site visit.
Permitted development in Canterbury
PD allows a lot of work without a planning application, but Canterbury's conservation overlay strips out several PD rights — rear extensions over 3m, side dormers and roof alterations visible from the street usually need full planning.
- • Single-storey rear extension: PD up to 3m (semi/terrace) or 4m (detached)
- • Loft dormer to rear: PD up to 40m³ (terrace 50m³ semi/detached), NOT in conservation areas
- • Front-facing alterations: almost always need planning in Canterbury's conservation area
- • Listed buildings: any external/internal alteration needs listed building consent
Canterbury local authority process
Applications are submitted via the local planning authority's portal. Typical determination is 8 weeks for householder applications. We pre-app with the planning officer on any project where the outcome looks borderline — saves a refused application and a 6-month restart.
Building regulations (separate from planning)
Whether or not you need planning, you'll need building regs sign-off. Structural calculations, fire safety, insulation U-values, drainage — all signed off by a Building Control Surveyor on completion. We handle every stage on Canterbury projects.
Find out if you need planning for house extensions in Canterbury
Free 30-minute site visit. We'll tell you straight whether it's PD, full planning, or listed-building consent — and what to expect from your local council.
Canterbury planning FAQs
How long does planning take in Canterbury?
8 weeks for a householder application from the local authority's date of validation. Add 2–3 weeks for pre-application advice if we use it. Listed building consent runs to a similar timeline but with stricter detail requirements.
What if my house is in the Canterbury conservation area?
Article 4 directions and conservation overlays remove some permitted development rights — rear dormers, side extensions and external materials all come under planning control. We design every detail around what we know the conservation officer will approve.
What about Article 4 directions near Canterbury Cathedral (UNESCO)?
Properties near Canterbury Cathedral (UNESCO) and inside the Canterbury conservation area lose specific PD rights. Materials, openings, render colour and external joinery all need formal approval. We've handled multiple submissions in this zone.
Can you submit the application for me?
Yes — drawings, planning statement, design & access statement, heritage statement (if listed) and submission to the local authority are all handled by our design team. You only sign the ownership certificate.
Related guides
Nearby areas we also cover
In short
Most house extension projects in Canterbury need planning input — conservation overlays around Canterbury Cathedral (UNESCO) are the main reason. We handle drawings, submission and officer liaison in-house.