Hounslow · Greater London

Kitchen extensions with bedrooms above in Hounslow

A kitchen extension with bedrooms above is one of the most space-efficient ways to add bedrooms and living space to a house in Hounslow, because the new floors share one set of foundations and one roof.

Quick reference for homeowners in Hounslow.

Postcode districts
TW2, TW3 and TW4
County / area
Greater London, England
Price region
London
Guide price
£67,000–£90,500 (£2,400–£3,240 per m²), kitchen units and worktops priced separately
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
Osterley (0.9 miles), Isleworth (0.9 miles), Heston (1.2 miles)
First visit
Free, no obligation

About a kitchen extension with bedrooms above

A kitchen extension with bedrooms above is a two-storey extension designed so the ground floor becomes a larger, usually open-plan kitchen and dining space, with one or two bedrooms or a bathroom on the first floor. It is a natural fit for a two-storey rear extension. The key design issues are the steel beams that open up the house, glazing and ventilation.

We cover postcode districts TW2, TW3 and TW4 in and around Hounslow, along with neighbouring Osterley, Isleworth and Heston.

What it costs in Hounslow

Our guide for London is £2,400–£3,240 per m² including VAT. On a project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that puts a kitchen extension with bedrooms above in Hounslow at roughly £67,000–£90,500 (kitchen units and worktops priced separately). Professional fees for drawings and the structural engineer are listed separately on our prices page.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£2,210–£2,980 per m²£62,000–£83,500
Standard£2,400–£3,240 per m²£67,000–£90,500
Premium£2,880–£3,890 per m²£80,500–£109,000

Planning and building regulations in Hounslow

In England, a two-storey rear kitchen extension can be permitted development if it goes no more than 3 m beyond the rear wall of the original house and stays at least 7 m from the rear boundary, with matching materials and roof pitch, outside protected areas. No balconies are allowed. Deeper designs 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 Hounslow homes

Bedrooms over a kitchen

Bedrooms above need an escape window or a protected route to the stairs, plus good sound insulation from the kitchen below. We position the stairs, landing and bedroom doors so the new rooms connect naturally to the existing first floor.

Services and drainage

Sinks, dishwashers and an upstairs bathroom all need waste routes to the drains, often near where the extension goes. We check the drains early and plan soil stacks, gas and electrical supplies so the kitchen layout is not limited later.

How we'd run your project

  1. Look at the house

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

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. On site

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

Questions about kitchen extensions with bedrooms above in Hounslow

How long does a kitchen extension with bedrooms above 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 kitchen extension with bedrooms above in Hounslow?

Hounslow 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 Hounslow?

We cover Hounslow (TW2, TW3 and TW4) and nearby places including Osterley, Isleworth and Heston, plus the rest of Greater London. The first site visit is free.

Is it cheaper to build a kitchen extension and bedrooms at the same time?

Yes, in most cases. Building both floors at once means one set of foundations, one roof, one scaffold and one set of approvals. Adding a first floor later means removing the original roof, possibly strengthening the foundations and disrupting the kitchen again. If you think you will need the bedroom, build it now.

Can I keep using my kitchen during the build?

For part of it. The new structure can be built while your existing kitchen stays in use, but when the rear wall is opened and the new kitchen is fitted there will be several weeks without one. We plan when this happens and help you set up a temporary kitchen elsewhere in the house.

Nearby

Close to Hounslow? We work across the area, including:

Other extensions in Hounslow

All two-storey extension services in Hounslow · Kitchen extensions with bedrooms above across Greater London

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