Two-storey front extensions in West Sussex

West Sussex at a glance

Nation: England
Price region: South East England
Postcode areas: BN, PO, RH
Towns covered: 19 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.

West Sussex towns we list: Crawley (RH10), Worthing (BN11), Bognor Regis (PO21), Littlehampton (BN17), Horsham (RH12) and Haywards Heath (RH16). Every other address in West Sussex is covered as well.

Guide price in South East England

Using our South East England rates, a two-storey front extension with a 3 m × 2 m footprint on two floors (12 m² of new floor space) comes to about £29,000–£39,500, including VAT. Bigger or more glazed designs cost more per m². The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	Typical project
Essential	£2,230–£3,040 per m²	£26,500–£36,500
Standard	£2,420–£3,300 per m²	£29,000–£39,500
Premium	£2,900–£3,960 per m²	£35,000–£47,500

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

Roof and gable design

A front extension is the most visible part of the house, so the roof needs to look deliberate: a matching gable, a hipped bay or a porch roof below a first-floor bay. We match the pitch and materials and keep the ridge below the main roof.

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.

How we work in West Sussex

Start at your house
We come to your home in West Sussex, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Drawings, then consent
We draw the scheme, check it against the rules in England, and take it through the right consent with the council.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Towns we cover in West Sussex

Two-storey front extensions in West Sussex: questions

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

In South East England our guide is £2,420–£3,300 per m² including VAT, so about £29,000–£39,500 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.

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.

Can I combine a front extension with a porch?

Yes. A common approach is a two-storey bay or gable with a single-storey porch roof running across the front door. This gives a bigger hall and front bedroom while breaking up the mass of the front wall. Both parts are covered by the same planning application and building regulations approval.

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 I need planning permission in West Sussex?

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

Neighbouring areas

All extension services in West Sussex · About two-storey front extensions