Part single, part two-storey extensions in Spitalfields
Adding a part single, part two-storey extension in Spitalfields gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.
The basics for Spitalfields at a glance.
- Postcode districts
- EC1Y, EC2, EC2A, EC2M, EC2N, EC2P and nearby districts
- 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
- Whitechapel (0.6 miles), Bethnal Green (0.7 miles), Shadwell (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 Spitalfields we also work in Whitechapel, Bethnal Green and Shadwell, and across the rest of Greater London. Postcode districts in and near Spitalfields: EC1Y, EC2, EC2A, EC2M, EC2N, EC2P and nearby districts.
What it costs in Spitalfields
In London, which includes Spitalfields, 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. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| 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 Spitalfields
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 Spitalfields homes
The roof junction
Where the single-storey roof meets the two-storey wall you need a sound weathering detail, usually a lead or similar flashing, and enough height for roof lights or a lantern. We set the roof falls and the upstairs window sill heights together so they do not clash.
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 Spitalfields, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build and sign-off
Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.
Questions about part single, part two-storey extensions in Spitalfields
Which postcodes do you cover around Spitalfields?
We cover Spitalfields (EC1Y, EC2, EC2A, EC2M, EC2N, EC2P and nearby districts) and nearby places including Whitechapel, Bethnal Green and Shadwell, plus the rest of Greater London. The first site visit is free.
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 Spitalfields?
Spitalfields 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.
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 Spitalfields
- Rear
- Side
- Wraparound
- Over a garage
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Spitalfields · Part single, part two-storey extensions across Greater London
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