Broadstairs · Kent

Part single, part two-storey extensions in Broadstairs

Want to stay in Broadstairs but need more space? A part single, part two-storey extension adds floor area on two levels without giving up much garden. Here's what's involved.

The basics for Broadstairs at a glance.

Postcode districts
CT10
County / area
Kent, England
Price region
South East England
Guide price
£79,000–£109,000 (£2,200–£3,030 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
Ramsgate (1.9 miles), Margate (2.9 miles), Birchington-on-Sea (6 miles)
Distance to Maidstone
about 40.5 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 district CT10 in and around Broadstairs, along with neighbouring Ramsgate, Margate and Birchington-on-Sea.

What it costs in Broadstairs

A guide price for Broadstairs: around £79,000–£109,000 for a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total). That works out at £2,200–£3,030 per m² of new floor space, including VAT at 20%. 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£2,020–£2,780 per m²£73,000–£100,000
Standard£2,200–£3,030 per m²£79,000–£109,000
Premium£2,640–£3,630 per m²£95,000–£130,500

Planning and building regulations in Broadstairs

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 Broadstairs 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.

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. Measure and listen

    A visit to Broadstairs to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.

  3. Structure and building control

    A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.

  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 Broadstairs

Which postcodes do you cover around Broadstairs?

We cover Broadstairs (CT10) and nearby places including Ramsgate, Margate and Birchington-on-Sea, plus the rest of Kent. 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.

Who handles building regulations for a project in Broadstairs?

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 Broadstairs? We work across the area, including:

Other extensions in Broadstairs

All two-storey extension services in Broadstairs · Part single, part two-storey extensions across Kent

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Broadstairs.

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