Stalybridge · Greater Manchester

Part single, part two-storey extensions in Stalybridge

A part single, part two-storey extension is one of the most space-efficient ways to add bedrooms and living space to a house in Stalybridge, because the new floors share one set of foundations and one roof.

Useful details for planning a part single, part two-storey extension in Stalybridge.

Postcode districts
SK15
County / area
Greater Manchester, England
Price region
North West England
Guide price
£68,500–£94,000 (£1,900–£2,610 per m²)
Approval route
It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
Nearest towns
Dukinfield (1.4 miles), Ashton-under-Lyne (1.7 miles), Mossley (2.3 miles)
Distance to Manchester
about 7.3 miles
First visit
Free, no obligation

About a part single, part two-storey extension

A part single, part two-storey extension suits you if you want a generous ground floor but only need one extra room upstairs, or if a full two-storey design would affect a neighbour too much. You get design options that test where the two-storey part works best, the approvals your nation needs, structural design, building regulations approval and the build, carried out by vetted teams working under S&K.

We cover Stalybridge (SK15) and the places around it, including Dukinfield (1.4 miles), Ashton-under-Lyne (1.7 miles) and Mossley.

What it costs in Stalybridge

For budgeting in Stalybridge, allow around £68,500–£94,000 for a part single, part two-storey extension with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total). That's based on £1,900–£2,610 per m² including VAT for North West England. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

SpecPer m²A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total)
Essential£1,750–£2,400 per m²£63,000–£86,500
Standard£1,900–£2,610 per m²£68,500–£94,000
Premium£2,280–£3,130 per m²£82,000–£113,000

Planning and building regulations in Stalybridge

In England, the extension can only be permitted development if it goes no more than 3 m beyond the original rear wall and stays at least 7 m from the rear boundary, with matching materials and roof pitch. We check the whole design against the rules, including the 50% garden coverage limit. If any part fails, or extends beyond a side wall on two floors, you need planning permission, costing £548 (or £575 for applications made from 8 December 2026).

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 Stalybridge homes

Where to put the two-storey part

The two-storey section usually works best away from the closest neighbour, with the single-storey part on that boundary side. We test a few positions against neighbours' windows, the upstairs layout and the roof shape before choosing the one to take forward.

Structure at the step

The first-floor wall above often sits over the new open-plan space, so it needs a steel beam or frame to carry it. Loads come down at different points than in a full two-storey design, and the engineer sizes the foundations to suit each part.

How we'd run your project

  1. Look at the house

    We start in Stalybridge with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about part single, part two-storey extensions in Stalybridge

How much does a part single, part two-storey extension cost in Stalybridge?

Our guide for North West England, which covers Stalybridge, is £1,900–£2,610 per m² including VAT. A typical project with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total) comes to about £68,500–£94,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

How long does a part single, part two-storey 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.

Which postcodes do you cover around Stalybridge?

We cover Stalybridge (SK15) and nearby places including Dukinfield, Ashton-under-Lyne and Mossley, plus the rest of Greater Manchester. The first site visit is free.

Which side should the two-storey part go on?

Usually the side furthest from the nearest neighbour's windows, so the single-storey part sits nearest them and keeps their light. Other factors are where the stairs land upstairs, which room needs the extra space and where drains run. We sketch options at the design stage and explain which is most likely to be approved.

Can the single-storey part be deeper than the two-storey part?

With planning permission, yes, and that is often the point of the design: the ground floor projects further into the garden while the first floor stays back from neighbours. Under permitted development, the depth limits for extensions of more than one storey can apply to the whole extension, so we confirm which route applies before drawings are finalised.

Nearby

We also cover places near Stalybridge, including:

Other extensions in Stalybridge

All two-storey extension services in Stalybridge · Part single, part two-storey extensions across Greater Manchester

Tell us about your house in Stalybridge and we'll call you back to arrange a free, no-obligation visit.

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