Side extensions across Christchurch
Thinking about a side extension for your Christchurch home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in ChristchurchFrom £22,000 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsBH5, BH6, BH7, BH23
What we take care of
- New openings through the side wall
- Foundations near boundaries and any drains
- Structure, roof tied into the house
- Windows, doors and finishes to match
- Survey, design and street-view drawings
- Planning route checked or application made
Councils often prefer side extensions to sit slightly back from the front of the house with a lower roof, so the original building still reads clearly. We design to those principles from the start to avoid redesigns.
Do I need planning permission in Christchurch?
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Side extension prices in Christchurch
Labour and material costs vary across the UK, so for Christchurch we use our South West England factor (×1.02). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Christchurch: £1,780 to £3,470 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £22,000 – £27,000 | £25,000 – £32,500 | £31,500 – £42,000 |
| 3 m × 6 m 18 m² | £32,000 – £39,000 | £37,500 – £49,000 | £47,500 – £62,500 |
| 3 m × 8 m 24 m² | £42,500 – £51,500 | £50,000 – £65,000 | £63,500 – £83,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Christchurch
Our survey diary covers Christchurch, including BH5, BH6, BH7, BH23. We also work in nearby Bournemouth (4 miles), Ferndown (7 miles), Poole (9 miles), Wimborne Minster (10 miles).
For homes towards Hampshire, New Milton is around 5 miles away. In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions people ask about side extensions
Do you cover all of Christchurch?
Yes. We cover Christchurch and the surrounding parts of Dorset. Site visits are free and there is no obligation.
How long does a side extension take to build in Christchurch?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Christchurch, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How close to the boundary can I build?
It depends on height. In England, within 2 m of a boundary the eaves must not exceed 3 m under permitted development. Building on the boundary is possible but brings party wall and maintenance access issues we plan for.
How much does a side extension cost?
Our guide range is about £1,780 to £3,470 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £37,500 to £49,000 in Christchurch.
Book a free site visit in Christchurch
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.