Two-storey side extensions in Haydock

Quick reference for homeowners in Haydock.

Postcode districts: WA11
County / area: Merseyside, England
Price region: North West England
Guide price: £82,000–£109,500 (£1,950–£2,610 per m²)
Approval route: Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns: Ashton-in-Makerfield (1.7 miles), St Helens (2.4 miles), Newton-le-Willows (3.6 miles)
Distance to Liverpool: about 12.8 miles
First visit: Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

Around Haydock we also work in Ashton-in-Makerfield, St Helens and Newton-le-Willows, and across the rest of Merseyside. Postcode district in and near Haydock: WA11.

What it costs in Haydock

Guide prices for two-storey side extensions in North West England are around £1,950–£2,610 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £82,000–£109,500. Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

Spec	Per m²	A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential	£1,790–£2,400 per m²	£75,500–£101,000
Standard	£1,950–£2,610 per m²	£82,000–£109,500
Premium	£2,340–£3,130 per m²	£98,000–£131,500

Planning and building regulations in Haydock

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

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 Haydock homes

Matching the ridge and roof

A hipped house usually needs a hipped extension roof, and a gabled house a gable. Matching the pitch, tiles, ridge detail and brick bond is what makes a side extension look original rather than added, and councils look closely at it on a front-facing addition.

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

How we'd run your project

Start at your house
We come to your home in Haydock, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Haydock.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about two-storey side extensions in Haydock

Who handles building regulations for a project in Haydock?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

Do I need planning permission for a two-storey side extension in Haydock?

Haydock is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How much does a two-storey side extension cost in Haydock?

Our guide for North West England, which covers Haydock, is £1,950–£2,610 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £82,000–£109,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

How long does a two-storey side extension take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Other towns near Haydock:

Other extensions in Haydock

All two-storey extension services in Haydock · Two-storey side extensions across Merseyside

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Haydock.