Two-storey front extensions in Dorset

Dorset at a glance

Nation: England
Price region: South West England
Postcode areas: BH, DT, SP
Towns covered: 16 listed below, plus surrounding villages
Approval route: Planning permission is needed: nothing can go forward of the front wall under permitted development.
Site visits: Free, no obligation

What a two-storey front extension involves

A two-storey front extension suits a house with a deep front garden or drive, where the back or side is not practical to extend. You get a design that respects the street, a planning application with drawings that show the extension in context, structural design, building regulations approval and the build, carried out by vetted teams working under S&K. At the free site visit we give you a frank view of whether the council is likely to accept it.

The main places we list in Dorset are Bournemouth (BH1), Poole (BH15), Weymouth (DT3), Christchurch (BH6), Ferndown (BH22) and Dorchester (DT1). We cover the villages in between too.

Guide price in South West England

In South West England, which includes Dorset, we'd expect a two-storey front extension to cost around £27,000–£37,000 for a 3 m × 2 m footprint on two floors (12 m² of new floor space), or £2,270–£3,090 per m² including VAT. Design fees, structural calculations and approval fees are separate and listed on our prices page.

Spec	Per m²	Typical project
Essential	£2,080–£2,840 per m²	£25,000–£34,000
Standard	£2,270–£3,090 per m²	£27,000–£37,000
Premium	£2,720–£3,710 per m²	£32,500–£44,500

Rules in England

In England, a two-storey front extension always needs householder planning permission, because permitted development does not allow any extension forward of the principal elevation. The fee is £548 (or £575 for applications made from 8 December 2026). Councils judge it mainly on design and the street scene, and should decide within 8 weeks of validation.

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.

The Party Wall etc. Act 1996 applies, so notices may be needed for work on or near a shared wall or boundary.

Getting the design right

Parking and access

Building forward can reduce off-road parking and the space for bins and meters. Councils may weigh up parking, so we check the drive will still work, along with the routes for gas, electricity and water supplies that often enter at the front.

Daylight to existing rooms

A front extension can make the hall and front rooms darker, especially if it covers an existing window. We position new windows to keep the house bright, and check that the new front bedroom gets good daylight without overlooking houses opposite.

How we work in Dorset

Measure and listen
A visit to Dorset to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Detail and price
Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Towns we cover in Dorset

Two-storey front extensions in Dorset: questions

How much does a two-storey front extension cost in Dorset?

In South West England our guide is £2,270–£3,090 per m² including VAT, so about £27,000–£37,000 for a 3 m × 2 m footprint on two floors (12 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.

Does a front extension affect my parking?

It can. If it is built over part of the drive you may lose a parking space, and some councils consider whether enough off-road parking remains. We measure the drive at the survey and show on the drawings how cars, bins and meters will fit after the work.

How far forward can a front extension go?

There is no fixed figure, because a two-storey front extension needs planning permission and the council decides case by case. Many councils' design guides favour a shallow projection that keeps a clear front garden. Our guide prices assume a modest example with a 3 m × 2 m footprint on two floors (12 m² of new floor space).

Will the council approve a two-storey front extension?

It depends on the street. Councils are more cautious about front extensions than rear ones because they change the street scene. Approval is more likely where the house is set back, the projection is modest, the design echoes the original house and similar additions already exist nearby. We give you a frank view at the free site visit.

Will I need planning permission in Dorset?

Dorset is in England. Planning permission is needed: nothing can go forward of the front wall under permitted development.

Neighbouring areas

All extension services in Dorset · About two-storey front extensions