Two-storey side extensions in Daventry
Homes in Daventry with a bit of space to the side or rear can often take a two-storey side extension. We'll tell you honestly whether yours can, and what approvals it needs.
Daventry: the key facts for this kind of project.
- Postcode districts
- NN11
- County / area
- Northamptonshire, England
- Price region
- East Midlands
- Guide price
- £84,500–£113,000 (£2,010–£2,700 per m²)
- Approval route
- Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
- Nearest towns
- Rugby (9 miles), Northampton (11.7 miles), Lutterworth (13.9 miles)
- Distance to Northampton
- about 11.7 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 Daventry (NN11) and the places around it, including Rugby (9.0 miles), Northampton (11.7 miles) and Lutterworth.
What it costs in Daventry
A guide price for Daventry: around £84,500–£113,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). That works out at £2,010–£2,700 per m² of new floor space, including VAT at 20%. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.
| Spec | Per m² | A 3 m × 7 m footprint on two floors (42 m² of new floor space) |
|---|---|---|
| Essential | £1,850–£2,480 per m² | £77,500–£104,000 |
| Standard | £2,010–£2,700 per m² | £84,500–£113,000 |
| Premium | £2,410–£3,230 per m² | £101,500–£136,000 |
Planning and building regulations in Daventry
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 Daventry homes
Access and services
Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.
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.
How we'd run your project
Free site visit
We visit your home in Daventry, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
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 Daventry
How much does a two-storey side extension cost in Daventry?
Our guide for the East Midlands, which covers Daventry, is £2,010–£2,700 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £84,500–£113,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
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.
Which postcodes do you cover around Daventry?
We cover Daventry (NN11) and nearby places including Rugby, Northampton and Lutterworth, plus the rest of Northamptonshire. The first site visit is free.
Do I need planning permission for a two-storey side extension in Daventry?
Daventry 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 Daventry, including:
Other extensions in Daventry
- 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 Daventry · Two-storey side extensions across Northamptonshire
Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.