East Sussex · BN7
Extensions in Lewes
A home extension adds new floor space to an existing property — commonly a rear or side-return kitchen extension, a wraparound, or a first-floor addition — and typically involves planning or permitted development approval, Building Regulations, and coordination of groundworks, structure, roofing and internal finishing.
In Lewes, that covers Cliffe, Southover, Landport, Nevill, Malling, Wallands. Lewes is the historic county town of East Sussex, built on a steep hillside above the River Ouse within the South Downs National Park, with a dense concentration of listed and historic buildings in its centre.
Coverage
Areas we cover in Lewes for extensions
Property styles in Lewes
The town centre includes a significant number of listed timber-framed, Georgian and Victorian buildings, often on constrained, steeply sloping plots, while the surrounding residential areas include Victorian terraces and 20th-century housing on the town's edges.
Planning considerations
Lewes District Council is the local planning authority, and the town sits within the South Downs National Park, which has its own planning authority function for certain matters and places significant weight on landscape and heritage impact. Much of the town centre is a conservation area with numerous listed buildings.
How it works
Our extensions process
- 01
Feasibility and survey
Assessing what is achievable on the plot, including boundary conditions, trees, drainage and neighbouring properties.
- 02
Design
Developing layout and elevations that work with the existing house, in scale and materials.
- 03
Planning route
Establishing whether the extension falls under permitted development or requires a full planning application, and submitting accordingly.
- 04
Party wall matters
Serving party wall notices where the extension is near a boundary, ahead of any groundworks starting.
- 05
Construction
Groundworks, structure, roof, and first fix through to decoration, with the existing house kept weathertight throughout.
- 06
Completion
Building Control sign-off, snagging list and handover.
Also in this area
Other services we provide in Lewes
Nearby coverage
Extensions in nearby areas
FAQs
Extensions in Lewes: FAQs
Do you provide extensions across all of Lewes?
Yes, we cover the BN7 postcode area in full, including Cliffe, Southover, Landport, Nevill, Malling, Wallands.
Do I need planning permission for a rear extension?
Many single-storey rear extensions fall under permitted development if they meet size, height and boundary criteria. Larger extensions, those on designated land, or properties where permitted development rights have been removed, need a full planning application. We assess this during the feasibility stage.
What is a party wall notice and do I need one?
If your extension involves work at or near a shared boundary, the Party Wall etc. Act 1996 usually requires you to notify your neighbour before work starts. We flag this during design so notices can be served in good time.
How does South Downs National Park status affect building work in Lewes?
Development within the National Park is assessed with particular regard to landscape character and setting, alongside normal planning policy. Combined with the town's conservation area and listed building status, this means early advice is particularly valuable in Lewes.
Get a quote for extensions in Lewes
Tell us about the property and what you have in mind, and we'll arrange a site visit.
Last reviewed 2026-07-19.