Single-storey extensions in Windsor

Covering Windsor

Windsor sits 16 miles east of Reading, with Slough 2 miles to the north and Egham 4 miles to the south-east.

Homes in the South East

Housing across the South East mixes inter-war semis, post-war estates and older cottages in villages and market towns, so rear and side extensions, hip-to-gable lofts and garage conversions all come up regularly.

What goes into 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.

Planning or lawful development certificate where needed
Building control application and inspections
First-fix and second-fix electrics, plastering and making good

What will a single-storey extension cost?

Use these ranges to budget for single-storey extensions; the survey turns them into a fixed price for the agreed specification.

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?

In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it 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 change the price or programme?

Drains under the footprint may need diverting or a build-over agreement with the water company.
Building on or near a shared boundary usually means serving a party wall notice in England and Wales.

What are the steps?

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
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.

Your questions answered

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.

Will the brick match?

We source the closest available match for colour, size and texture and agree a sample panel with you before laying.

Who deals with the council for a project in Windsor?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Other towns nearby

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