Single-storey extensions · St Helens

Single-storey extensions in St Helens

Our single-storey extensions service covers St Helens and the rest of Merseyside. You get a fixed price in writing for the agreed specification, and one person co-ordinating the trades.

Covering St Helens

We work in St Helens (WA10) and the places around it, including Prescot, Ashton-in-Makerfield and Huyton.

Homes in the North West

The North West has long rows of Victorian terraced houses in its towns and cities, alongside inter-war semis and post-war estates, so rear extensions, dormer lofts and kitchen extensions are common projects.

What does a single-storey extension involve?

A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.

  • Measured survey and design drawings
  • Building control application and inspections
  • Foundations, drainage and structural steel

How much does a single-storey extension cost in St Helens?

Typical ranges for single-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Single-storey extensionsGuide price incl. VAT
Standard specification£2,600 to £3,000 per m²
Good specification£3,000 to £3,500 per m²
High specification£3,500 to £4,000 per m²

How is a single-storey extension approved in St Helens?

In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary. Deeper extensions, up to 6 m or 8 m, need prior approval from the council first.

What should I think about before starting?

  • Drains under the footprint may need diverting or a build-over agreement with the water company.
  • Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.

From first call to completion

  1. Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
  2. Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
  3. Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
  4. Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

Questions about a single-storey extension in St Helens

Can we stay in the house during the build?

Usually yes. We keep the existing house closed off from the works until the knock-through near the end, and agree a temporary kitchen set-up with you if the kitchen is affected.

Will the brick match?

We source the closest available match for colour, size and texture and agree a sample panel with you before laying.

How do I get a price for single-storey extensions in St Helens?

Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.

Single-storey extensions near St Helens

Learn more about single-storey extensions, or see every project we cover in St Helens.

Planning an extension, loft or new home?

Get a guide price in two minutes, then book a free site visit.

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