Cost of a house extension in Brighton (Per m² Guide)

Cost of a house Extension in Brighton (Per m² Guide)

A house extension is one of the biggest investments most homeowners make, but it can completely transform how your home works and often adds significant value too.

In Brighton, most extensions cost somewhere between £2,000 and £4,000+ per m², depending on the type of extension, finish, and structural work involved.

Smaller single-storey builds naturally cost less than large rear or double-storey extensions with high-end finishes.

Average Cost

£25000- 150000+

Typical Timeframe

2-8 Months

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Typical kitchen fitting costs in Brighton

Extension

Average Cost

Small single-storey extension

£25000- 45000

Mid-size extension

£45000- 70000

Large or high-end extension

£70000- 150000+

*prices are estimates based on standard installation in the Brighton area

Labour vs materials

Most extension projects break down roughly as:

Labour: 40–50%
Materials: 50–60%

Material costs have increased significantly in recent years, especially timber and steel.

Common extras (often overlooked)

Architect drawings

Structural engineer

building control fees

Kitchen installation

Landscaping after the build

What affects the cost the most?

Extensions vary hugely in price depending on:

Size of the extension
Type of build
Ground conditions
Structural steel requirements
Kitchen or bathroom additions
Quality of finish
Planning and design complexity

Rear extensions are usually more straightforward than side-return or wraparound builds.

Local insight: Extensions in Brighton homes

Building an extension in Brighton can come with extra challenges compared to newer areas.

A lot of Brighton homes are:

Victorian or period properties
In conservation areas
Built on slopes or difficult ground

This can lead to:

More structural work
Harder access for machinery/materials
Additional planning restrictions

Parking restrictions and limited side access are also common and can affect labour time