Faversham · Kent

Two-storey extensions for semi-detached houses in Faversham

Adding a two-storey extension for a semi-detached house in Faversham gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Useful details for planning a two-storey extension for a semi-detached house in Faversham.

Postcode districts
ME13
County / area
Kent, England
Price region
South East England
Guide price
£61,500–£83,000 (£2,200–£2,970 per m²)
Approval route
Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission.
Nearest towns
Whitstable (6.7 miles), Sittingbourne (7 miles), Canterbury (8.6 miles)
Distance to Maidstone
about 16.4 miles
First visit
Free, no obligation

About a two-storey extension for a semi-detached house

A two-storey extension for a semi-detached house is a two-floor addition to the rear, the open side, or both, designed around the attached neighbour on one side. The rear is often the simplest option and can sometimes be permitted development, while a side extension uses the gap on the detached side. Both need care with the shared party wall and the neighbour's light.

We cover postcode district ME13 in and around Faversham, along with neighbouring Whitstable, Sittingbourne and Canterbury.

What it costs in Faversham

Expect a two-storey extension for a semi-detached house in Faversham to land somewhere around £61,500–£83,000 for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). Our South East England guide rate is £2,200–£2,970 per m², including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£2,020–£2,730 per m²£56,500–£76,500
Standard£2,200–£2,970 per m²£61,500–£83,000
Premium£2,640–£3,560 per m²£74,000–£100,000

Planning and building regulations in Faversham

In England, a two-storey rear extension on a semi can be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary, with matching materials and roof pitch. A two-storey side or wraparound extension always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026). Protected areas such as conservation areas exclude two-storey rear permitted development.

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 Faversham homes

Rear, side or both

On a semi, a rear extension sits against the attached neighbour, while a side extension faces the detached neighbour and the street. We compare the space, cost and approval route for each, and for a wraparound, before you commit to one design.

Keeping the pair balanced

Semis are designed as matching pairs, and a side extension changes that balance. Setting the side extension back from the front wall and keeping its ridge lower helps the pair still read as a pair, which councils' design guides commonly ask for.

How we'd run your project

  1. Free site visit

    We visit your home in Faversham, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey extensions for semi-detached houses in Faversham

Do I need planning permission for a two-storey extension for a semi-detached house in Faversham?

Faversham is in England, so England planning rules apply. Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How much does a two-storey extension for a semi-detached house cost in Faversham?

Our guide for South East England, which covers Faversham, is £2,200–£2,970 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £61,500–£83,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Which postcodes do you cover around Faversham?

We cover Faversham (ME13) and nearby places including Whitstable, Sittingbourne and Canterbury, plus the rest of Kent. The first site visit is free.

Should I extend my semi to the side or the rear?

It depends on your plot and what you need. A rear extension keeps the side drive and can sometimes be permitted development, but it affects the attached neighbour. A side extension keeps the rear garden but always needs planning permission in England. We compare both at the free site visit.

Does a two-storey extension add value to a semi-detached house?

It usually adds value, but the gain is never certain. Nationwide's 2025 research found that 10% more floor area was linked to about 5% higher value, and that adding a double bedroom and bathroom to a three-bed, one-bathroom house could add up to 24%. Every street has a ceiling price, so check local sales first.

Nearby

Other towns near Faversham:

Other extensions in Faversham

All two-storey extension services in Faversham · Two-storey extensions for semi-detached houses across Kent

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