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Cornwall

Rear extensions for bungalows in Cornwall

Single-storey rear extensions that keep everything on one level. Rear extensions in Cornwall: we cover 10 towns including Redruth, Falmouth and St Austell, with design, approvals and the build under one contract.

Bungalow with a pitched-roof rear extension, two roof windows and grey French doors onto a patio

For bungalows in Cornwall, a rear extension is the usual way to add space without adding stairs. Stone-built and rendered houses are common around Cornwall, so matching the walling is a design decision in its own right: natural stone, reconstituted stone or a render finish across old and new.

How much does a bungalow rear extension cost in Cornwall?

Guide prices for a bungalow rear extension in Cornwall start from our South West England rate of £1,920–£3,120 per square metre, including VAT. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.

Bungalow rear extension guide prices in Cornwall
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£23,000–£37,500
4 m wide × 6 m deep (24 m²)£46,000–£75,000

Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.

Do you need planning permission in Cornwall?

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.

If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.

Where in Cornwall do we work?

FAQ

Questions people ask

Can a bungalow extension be fully accessible?

Yes: level thresholds, wider doors and a wet room are straightforward to design in.

Will the roof look odd?

Not if the pitch and tiles match. Where the eaves are low, a flat-roofed section with a lantern is an alternative.

Can I extend the loft as well?

Sometimes, but that is a different project; a rear extension keeps everything on one level.

Do you cover all of Cornwall?

We cover 10 towns and districts in Cornwall, including Redruth, Falmouth and St Austell.

Who builds the extension?

Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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