Uppermill · Greater Manchester

Part single, part two-storey extensions in Uppermill

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 Uppermill, because the new floors share one set of foundations and one roof.

What we'd confirm first for a project in Uppermill.

Postcode districts
OL3
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
Saddleworth (0 miles), Mossley (2.6 miles), Lees (2.9 miles)
Distance to Manchester
about 10.6 miles
First visit
Free, no obligation

About a part single, part two-storey extension

A part single, part two-storey extension is an extension where the ground floor is wider or deeper than the floor above, so only part of it rises to two storeys. It usually gives a large kitchen or living area with roof lights below and one bedroom or bathroom above. It is often a good way to add space while limiting the effect on neighbours.

We cover Uppermill (OL3) and the places around it, including Saddleworth (0.0 miles), Mossley (2.6 miles) and Lees.

What it costs in Uppermill

In North West England, which includes Uppermill, we'd expect a part single, part two-storey extension to cost around £68,500–£94,000 for a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total), or £1,900–£2,610 per m² including VAT. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

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 Uppermill

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 Uppermill homes

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.

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.

How we'd run your project

  1. Understand the brief

    At your home in Uppermill we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  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 Uppermill

Which postcodes do you cover around Uppermill?

We cover Uppermill (OL3) and nearby places including Saddleworth, Mossley and Lees, plus the rest of Greater Manchester. The first site visit is free.

Do I need planning permission for a part single, part two-storey extension in Uppermill?

Uppermill is in England, so England planning rules apply. 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. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

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.

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.

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.

Nearby

Close to Uppermill? We work across the area, including:

Other extensions in Uppermill

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

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

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