Side extensions in Dunstable: design, approvals and build
Planning a side extension in Dunstable? We survey the house, work out the planning route, draw the design and build it, so you deal with one team from the first visit to the completion certificate.
- Guide price in DunstableFrom £23,000 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsLU4, LU5, LU6
What should I budget for a side extension in Dunstable?
Labour and material costs vary across the UK, so for Dunstable we use our East of England factor (×1.06). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Dunstable: £1,860 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £23,000 – £28,000 | £26,000 – £34,000 | £33,000 – £43,500 |
| 3 m × 6 m 18 m² | £33,000 – £40,500 | £39,000 – £51,000 | £49,500 – £65,000 |
| 3 m × 8 m 24 m² | £44,500 – £53,500 | £52,000 – £67,500 | £66,000 – £86,500 |
For a figure based on your own dimensions, use our guide-price tool.
Do I need planning permission in Dunstable?
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Working in Dunstable
Across LU4, LU5, LU6, we can visit, measure and advise. Nearby, we also take on projects in Luton (5 miles), Leighton Buzzard (6 miles), Ampthill (10 miles), Kempston (16 miles).
Harpenden, in Hertfordshire, is roughly 9 miles from Dunstable and also on our list. The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
Is a side extension right for your house?
- Houses where the rear garden is small
- Detached and semi-detached houses with side land
- Homes needing a utility, study or ground-floor bedroom
What happens next
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Side extension questions answered
Who do I contract with for a side extension in Dunstable?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Do you cover all of Dunstable?
Yes. We cover Dunstable and the surrounding parts of Bedfordshire. Site visits are free and there is no obligation.
How long does a side extension take to build in Dunstable?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
How close to the boundary can I build?
It depends on height. In England, within 2 m of a boundary the eaves must not exceed 3 m under permitted development. Building on the boundary is possible but brings party wall and maintenance access issues we plan for.
How much does a side extension cost?
Our guide range is about £1,860 to £3,600 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £39,000 to £51,000 in Dunstable.
Book a free site visit in Dunstable
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.