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England

Rear extensions in Merseyside

Across Merseyside we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Liverpool, St Helens and Southport.

Rear extension on a house typical of the area

What are homes in Merseyside like to extend?

Merseyside has long runs of terraced houses with back yards and alleys, plus 1930s semis further out. Yard extensions on terraces are often single-storey and close to both boundaries.

Rear extension prices in Merseyside

North West prices sit below our West Midlands baseline; access on terraced streets is the main variable. Per square metre including VAT, standard specification:

ExtensionPer m²
Single-storey rear extension£1,790–£2,910
Two-storey (per m² across both floors)£1,690–£2,540
Side return£2,160–£3,570
Wraparound£2,070–£3,380
Glass-led£2,630–£4,510

Planning and building rules in Merseyside

Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.

The Party Wall etc. Act 1996 applies in England: you serve notice two months before work to a shared wall, and one month before digging foundations within 3 metres (or 6 metres for deeper foundations) of a neighbour's building. Neighbours can agree in writing; if they dissent, surveyors agree an award.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.

Rear extensions we build in Merseyside

Towns and districts in Merseyside

The main places we cover in Merseyside include Liverpool, St Helens and Southport, across postcode areas CH, FY, L and WA.

Main towns in Merseyside
TownPostcode districtsNearest town we also cover
LiverpoolL5, L8, L9Kensington (1.0 miles)
St HelensWA9, WA10, WA11Haydock (2.4 miles)
SouthportL22, L30, L37Formby (6.5 miles)
BirkenheadCH41, CH42, CH43Liverpool (1.9 miles)
WallaseyCH44, CH45Moreton (2.7 miles)
BootleL20, L21, L22Litherland (0.8 miles)
BebingtonCH42, CH62, CH63Bromborough (1.5 miles)
HuytonL28, L34, L36Belle Vale (1.6 miles)
KirkbyL32, L33Fazakerley (2.0 miles)
PrescotL28, L34, L36Whiston (0.8 miles)

Areas near Merseyside

FAQ

Questions people ask

How much does a rear extension cost in Merseyside?

As a guide, £1,790–£2,910 per square metre including VAT for a standard single-storey extension at North West England rates.

Do I need planning permission in Merseyside?

Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.

Which towns in Merseyside do you cover?

41 towns and districts, including Liverpool, St Helens and Southport.

Do you handle building control?

Yes. We apply to the council or a registered building control approver and hand over the completion certificate.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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