Milton Keynes · Buckinghamshire

Kitchen extensions with bedrooms above in Milton Keynes

Adding a kitchen extension with bedrooms above in Milton Keynes 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.

Quick reference for homeowners in Milton Keynes.

Postcode districts
MK5, MK6, MK8, MK9, MK10, MK11 and nearby districts
County / area
Buckinghamshire, England
Price region
South East England
Guide price
£61,500–£83,000 (£2,200–£2,970 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
Newport Pagnell (3.5 miles), Bletchley (3.5 miles), Leighton Buzzard (9.6 miles)
First visit
Free, no obligation

About a kitchen extension with bedrooms above

This service suits you if your kitchen is too small and you also need another bedroom. Building both floors at once costs less than a single-storey kitchen extension now and a first floor later. You get a layout that works for cooking, eating and the garden, a bedroom plan that works upstairs, the approvals your nation needs and the build, carried out by vetted teams working under S&K. Kitchen units are priced separately.

Around Milton Keynes we also work in Newport Pagnell, Bletchley and Leighton Buzzard, and across the rest of Buckinghamshire. Postcode districts in and near Milton Keynes: MK5, MK6, MK8, MK9, MK10, MK11 and nearby districts.

What it costs in Milton Keynes

For budgeting in Milton Keynes, allow around £61,500–£83,000 (kitchen units and worktops priced separately) for a kitchen extension with bedrooms above with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). That's based on £2,200–£2,970 per m² including VAT for South East England. Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£2,020–£2,730 per m²£56,500–£76,500
Standard£2,200–£2,970 per m²£61,500–£83,000
Premium£2,640–£3,560 per m²£74,000–£100,000

Planning and building regulations in Milton Keynes

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 Milton Keynes 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.

Glazing and the Part L 25% rule

In England, new windows, roof lights and glazed doors in an extension are normally limited to 25% of the extension's floor area plus the area of any windows or doors removed. Larger glazing is possible, but needs SAP or compensating calculations, so we plan the rear doors around this from the start.

How we'd run your project

  1. Free site visit

    We visit your home in Milton Keynes, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Get it approved

    Once you're happy with the design we submit it to the council for Milton Keynes and deal with any questions from the planning officer.

  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. 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 kitchen extensions with bedrooms above in Milton Keynes

Do I need planning permission for a kitchen extension with bedrooms above in Milton Keynes?

Milton Keynes 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 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.

Which postcodes do you cover around Milton Keynes?

We cover Milton Keynes (MK5, MK6, MK8, MK9, MK10, MK11 and nearby districts) and nearby places including Newport Pagnell, Bletchley and Leighton Buzzard, plus the rest of Buckinghamshire. 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

We also cover places near Milton Keynes, including:

Other extensions in Milton Keynes

All two-storey extension services in Milton Keynes · Kitchen extensions with bedrooms above across Buckinghamshire

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.

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