Part single, part two-storey extensions in Brixton Hill

Before you start in Brixton Hill, here's what applies.

Postcode districts: SW2
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: Clapham (0.9 miles), Brixton (1.2 miles), Balham (1.2 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.

Around Brixton Hill we also work in Clapham, Brixton and Balham, and across the rest of Greater London. Postcode district in and near Brixton Hill: SW2.

What it costs in Brixton Hill

A guide price for Brixton Hill: around £86,500–£119,000 for a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total). That works out at £2,400–£3,300 per m² of new floor space, including VAT at 20%. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	A 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 Brixton Hill

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 Brixton Hill homes

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.

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

Start at your house
We come to your home in Brixton Hill, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Questions about part single, part two-storey extensions in Brixton Hill

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

Brixton Hill 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 postcodes do you cover around Brixton Hill?

We cover Brixton Hill (SW2) and nearby places including Clapham, Brixton and Balham, plus the rest of Greater London. The first site visit is free.

Who handles building regulations for a project in Brixton Hill?

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.

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.

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 Brixton Hill? We work across the area, including:

Other extensions in Brixton Hill

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

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