Flat roof extensions across Kettering
Thinking about a flat roof extension for your Kettering home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in KetteringFrom £19,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsNN14, NN15, NN16
Do I need planning permission in Kettering?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
The planning position for a specific Kettering address depends on its history and any designations, which is why we check it at the first visit.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
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).
When a flat roof extension makes sense
- Extensions under first-floor windows where a pitch will not fit
- Modern and 1930s onwards houses
- Homeowners who want maximum light from above
What should I budget for a flat roof extension in Kettering?
For Kettering we adjust our national guide rates by ×0.95, the factor we use for East Midlands. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Kettering: £1,660 to £3,180 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £19,500 – £23,500 | £23,000 – £30,000 | £29,500 – £38,500 |
| 4 m × 5 m 20 m² | £33,000 – £39,000 | £38,500 – £49,500 | £49,000 – £64,000 |
| 5 m × 6 m 30 m² | £49,500 – £58,500 | £58,000 – £74,500 | £74,000 – £95,500 |
For a figure based on your own dimensions, use our guide-price tool.
Extensions in and around Kettering
Postcode districts we cover around Kettering include NN14, NN15, NN16. We also work in nearby Wellingborough (7 miles), Corby (7 miles), Rushden (9 miles), Market Harborough (10 miles).
Just over the Rutland border, Oakham is about 18 miles away. The East Midlands has plenty of inter-war and post-war semis and detached houses with room to extend, alongside Victorian terraces in the towns.
Our process, step by step
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
We visit your Kettering home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions people ask about flat roof extensions
How long does a flat roof extension take to build in Kettering?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Do you cover all of Kettering?
Yes. We cover Kettering and the surrounding parts of Northamptonshire. Site visits are free and there is no obligation.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Kettering, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can I walk on a flat roof extension?
Only for maintenance unless it is designed as a terrace. A roof terrace or balcony needs planning permission and a different structure.
Are flat roof extensions cheaper?
Usually slightly, because there is less roof structure and no tiles. Our guide range is about £1,660 to £3,180 per m² including VAT.
Book a free site visit in Kettering
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.