Shepherds Bush · Greater London

Part single, part two-storey extensions in Shepherds Bush

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

Quick reference for homeowners in Shepherds Bush.

Postcode districts
W6 and W12
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
Notting Hill (0.8 miles), Earls Court (1.4 miles), Bayswater (1.6 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 postcode districts W6 and W12 in and around Shepherds Bush, along with neighbouring Notting Hill, Earls Court and Bayswater.

What it costs in Shepherds Bush

In London, which includes Shepherds Bush, we'd expect a part single, part two-storey extension to cost 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), or £2,400–£3,300 per m² including VAT. Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

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 Shepherds Bush

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 Shepherds Bush 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.

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. Start at your house

    We come to your home in Shepherds Bush, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  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. Engineer it

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

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about part single, part two-storey extensions in Shepherds Bush

Which postcodes do you cover around Shepherds Bush?

We cover Shepherds Bush (W6 and W12) and nearby places including Notting Hill, Earls Court and Bayswater, plus the rest of Greater London. The first site visit is free.

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

Shepherds Bush 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 much does a part single, part two-storey extension cost in Shepherds Bush?

Our guide for London, which covers Shepherds Bush, is £2,400–£3,300 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 £86,500–£119,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

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.

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

The same service in neighbouring towns:

Other extensions in Shepherds Bush

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

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