Single-storey extensions in Devon

Covering Devon

Our single-storey extensions service in Devon covers Plymouth, Exeter, Paignton and Torquay and more.

Homes in the South West

In the South West, matching local stone, render or slate is often the main design question, and conservation areas and listed buildings are common in historic towns.

What do you get with a single-storey extension?

A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.

Measured survey and design drawings
Planning or lawful development certificate where needed
Brickwork, roof, glazing and insulation

How much does a single-storey extension cost in Devon?

Indicative costs for single-storey extensions. London and the South East usually sit towards the top of each range.

Single-storey extensions	Guide price incl. VAT
Standard specification	£2,600 to £3,000 per m²
Good specification	£3,000 to £3,500 per m²
High specification	£3,500 to £4,000 per m²

What approvals does a single-storey extension need in England?

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.

What can affect a single-storey extension?

Building on or near a shared boundary usually means serving a party wall notice in England and Wales.
Kitchens and doors have long lead times, so we order them early.

What are the steps?

Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Single-storey extensions: common questions

How much does a single-storey extension cost?

Most single-storey extensions cost about £2,600 to £4,000 per square metre including VAT, depending on specification, glazing and ground conditions. We give a fixed price in writing for the agreed specification after the survey.

Do I need planning permission for a single-storey extension?

Often not in England, if the extension stays within permitted development limits: 3 m deep on an attached house or 4 m on a detached house, and no higher than 4 m. Larger ones need prior approval or a planning application. Wales, Scotland and Northern Ireland have their own rules.

Can you visit a house in Devon to quote?

Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.

Single-storey extensions near Devon

Learn more about single-storey extensions, or see every project we cover in Devon.