Upper Norwood · Greater London

Part single, part two-storey extensions in Upper Norwood

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

The basics for Upper Norwood at a glance.

Postcode districts
SE19
County / area
Greater London, England
Price region
London
Guide price
£86,500–£119,000 (£2,400–£3,300 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
Crystal Palace (0.7 miles), Gipsy Hill (0.9 miles), Norbury (1 mile)
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.

Around Upper Norwood we also work in Crystal Palace, Gipsy Hill and Norbury, and across the rest of Greater London. Postcode district in and near Upper Norwood: SE19.

What it costs in Upper Norwood

For budgeting in Upper Norwood, allow around £86,500–£119,000 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 £2,400–£3,300 per m² including VAT for London. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total)
Essential£2,210–£3,040 per m²£79,500–£109,500
Standard£2,400–£3,300 per m²£86,500–£119,000
Premium£2,880–£3,960 per m²£103,500–£142,500

Planning and building regulations in Upper Norwood

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 Upper Norwood 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.

Light into the kitchen

The single-storey part is the place for roof lights or a lantern, which bring daylight deep into the plan. In England, glazing is normally limited to 25% of the new floor area plus any windows removed, unless calculations show the house still performs, so we plan the balance early.

How we'd run your project

  1. Look at the house

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

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Upper Norwood.

  3. Engineer it

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

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about part single, part two-storey extensions in Upper Norwood

Who handles building regulations for a project in Upper Norwood?

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.

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.

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

Upper Norwood 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.

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 I add roof lights to the single-storey part?

Yes. Roof lights or a lantern over the single-storey part are one of the main reasons to choose this design, as they light the middle of a deep kitchen. In England they count towards the Part L glazing allowance, normally 25% of the new floor area plus windows removed, so we balance them with the rear doors.

Nearby

Other towns near Upper Norwood:

Other extensions in Upper Norwood

All two-storey extension services in Upper Norwood · Part single, part two-storey extensions across Greater London

The quickest next step is a visit. We'll look at your house in Upper Norwood and give you an honest view of the options.

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