St Helens, Merseyside
Terraced house rear extension in St Helens
For homes in St Helens, a terraced house rear extension is often the simplest way to gain space without moving. Rear and side return extensions for terraces, with access through the house and two neighbours. We take it from survey to completion certificate.
St Helens and its postcode districts WA9, WA10 and WA11 are part of our Merseyside coverage. In St Helens we plan the delivery route through the house and the skip licence before anything else.
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 terraced house rear extension cost in St Helens?
For St Helens we work from the North West England rate: £1,930–£3,100 per square metre of new floor, including VAT, standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £26,000–£42,000 |
| 3 m wide × 6 m deep (18 m²) | £34,500–£56,000 |
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 terraced house rear extension in St Helens?
Here is how the rules in England apply to a terraced house rear extension in St Helens.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
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. 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 St Helens like to extend?
Stone and brick terraces are common around St Helens. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
How a terraced house rear extension in St Helens comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Terraced house rear extensions near St Helens
We also build rear extensions for terraced houses in nearby Haydock (2.4 miles) and Rainhill (2.7 miles).
- Terraced house rear extension in Haydock
- Terraced house rear extension in Rainhill
- Terraced house rear extension in Whiston
- Terraced house rear extension in Prescot
- Terraced house rear extension in Ashton in Makerfield
Other work in St Helens:
FAQ
Terraced house rear extension questions in St Helens
What postcode areas do you cover around St Helens?
Including WA9, WA10 and WA11, and the surrounding Merseyside area.
Do I need planning permission for a rear extension in St Helens?
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.
Can you build without side access?
Yes. Materials come through the house in protected runs or over the roof by crane on tight sites.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How long does a rear extension take to build in St Helens?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.