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Wallasey, Merseyside

Semi-detached rear extension in Wallasey

Thinking about a semi-detached rear extension in Wallasey? Single or two-storey extensions for semi-detached houses, with side access and one party wall. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.

Wallasey and its postcode districts CH44 and CH45 are part of our Merseyside coverage. Where a Wallasey semi already has a small lean-to at the back, we usually replace it rather than extend it.

Book a free site visit

Tell us about the house and we'll call to arrange a free, no-obligation visit.

How much does a semi-detached rear extension cost in Wallasey?

In Wallasey, our guide for a semi-detached rear extension is £1,790–£2,910 per square metre including VAT for a standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.

Semi-detached rear extension prices in Wallasey
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£21,500–£35,000
4 m wide × 5 m deep (20 m²)£35,500–£58,500
4 m wide × 6 m deep (24 m²)£43,000–£70,000

Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.

Do you need planning permission for a semi-detached rear extension in Wallasey?

Planning for a semi-detached rear extension in Wallasey follows the English householder rules.

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

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.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.

What are homes in Wallasey like to extend?

Wallasey 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.

How a semi-detached rear extension in Wallasey comes together

  1. Survey visit

    We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.

  2. Options and costs

    We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

  3. Planning and regulations

    We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.

  4. Build and sign-off

    We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.

Semi-detached rear extensions near Wallasey

Close by, we work in Moreton, about 2.7 miles away, and Birkenhead, about 2.9 miles away.

Other work in Wallasey:

All rear extensions in Wallasey

FAQ

Semi-detached rear extension questions in Wallasey

Can you match the brick or stone on my Wallasey house?

We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.

Is the site visit in Wallasey free?

Yes. We visit, measure up and talk through the options with no cost and no obligation.

What if my neighbour has already extended?

That can make a matching depth easier to justify. We measure theirs at the survey.

How much does a semi-detached rear extension cost in Wallasey?

As a guide, £1,790–£2,910 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,500–£35,000 at that rate. Your written price follows the survey.

Who will build my extension?

Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.

Do I need a party wall agreement?

In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.

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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