Two-storey side extensions in Ampthill
Our two-storey side extensions service in Ampthill covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Useful details for planning a two-storey side extension in Ampthill.
- Postcode districts
- MK45
- County / area
- Bedfordshire, England
- Price region
- East of England
- Guide price
- £88,500–£119,000 (£2,110–£2,830 per m²)
- Approval route
- Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
- Nearest towns
- Flitwick (1.6 miles), Kempston Hardwick (4.3 miles), Kempston (6.2 miles)
- Distance to Luton
- about 10.7 miles
- First visit
- Free, no obligation
About a two-storey side extension
A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.
We cover postcode district MK45 in and around Ampthill, along with neighbouring Flitwick, Kempston Hardwick and Kempston.
What it costs in Ampthill
Expect a two-storey side extension in Ampthill to land somewhere around £88,500–£119,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Our East of England guide rate is £2,110–£2,830 per m², including VAT. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.
| Spec | Per m² | A 3 m × 7 m footprint on two floors (42 m² of new floor space) |
|---|---|---|
| Essential | £1,940–£2,610 per m² | £81,500–£109,500 |
| Standard | £2,110–£2,830 per m² | £88,500–£119,000 |
| Premium | £2,530–£3,400 per m² | £106,500–£143,000 |
Planning and building regulations in Ampthill
In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.
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 Ampthill homes
Matching the ridge and roof
A hipped house usually needs a hipped extension roof, and a gabled house a gable. Matching the pitch, tiles, ridge detail and brick bond is what makes a side extension look original rather than added, and councils look closely at it on a front-facing addition.
Set-down and set-back
Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.
How we'd run your project
Understand the brief
At your home in Ampthill we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Drawings, then consent
We draw the scheme, check it against the rules in England, and take it through the right consent with the council.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.
Questions about two-storey side extensions in Ampthill
Which postcodes do you cover around Ampthill?
We cover Ampthill (MK45) and nearby places including Flitwick, Kempston Hardwick and Kempston, plus the rest of Bedfordshire. The first site visit is free.
How long does a two-storey side 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 Ampthill?
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.
Do I need planning permission for a two-storey side extension in Ampthill?
Ampthill is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.
Can I build a two-storey side extension over my driveway?
Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.
Nearby
We also cover places near Ampthill, including:
Other extensions in Ampthill
- Rear
- Wraparound
- Part two-storey
- Over a garage
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Ampthill · Two-storey side extensions across Bedfordshire
Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Ampthill.