Ferndown · Dorset

Two-storey side extensions in Ferndown

Homes in Ferndown with a bit of space to the side or rear can often take a two-storey side extension. We'll tell you honestly whether yours can, and what approvals it needs.

What we'd confirm first for a project in Ferndown.

Postcode districts
BH22
County / area
Dorset, England
Price region
South West England
Guide price
£88,500–£119,000 (£2,110–£2,830 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Wimborne Minster (4 miles), Verwood (4.9 miles), Canford Heath (4.9 miles)
Distance to Bournemouth
about 6.1 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

Around Ferndown we also work in Wimborne Minster, Verwood and Canford Heath, and across the rest of Dorset. Postcode district in and near Ferndown: BH22.

What it costs in Ferndown

Expect a two-storey side extension in Ferndown to land somewhere around £88,500–£119,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Our South West England guide rate is £2,110–£2,830 per m², including VAT. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,940–£2,610 per m²£81,500–£109,500
Standard£2,110–£2,830 per m²£88,500–£119,000
Premium£2,530–£3,400 per m²£106,500–£143,000

Planning and building regulations in Ferndown

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Ferndown homes

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

Access and services

Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.

How we'd run your project

  1. Look at the house

    We start in Ferndown with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.

  3. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. Build and sign-off

    Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Questions about two-storey side extensions in Ferndown

Who handles building regulations for a project in Ferndown?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

How much does a two-storey side extension cost in Ferndown?

Our guide for South West England, which covers Ferndown, is £2,110–£2,830 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £88,500–£119,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a two-storey side extension in Ferndown?

Ferndown is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Which postcodes do you cover around Ferndown?

We cover Ferndown (BH22) and nearby places including Wimborne Minster, Verwood and Canford Heath, plus the rest of Dorset. The first site visit is free.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Close to Ferndown? We work across the area, including:

Other extensions in Ferndown

All two-storey extension services in Ferndown · Two-storey side extensions across Dorset

Want a figure first? Try our guide price tool, then book a free visit to firm it up.

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