Pitched roof extensions in Dover: design, approvals and build
From the first sketch to final sign-off, we plan and build pitched roof extensions in Dover and the surrounding Kent area.
- Guide price in DoverFrom £24,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsCT16, CT17

Planning rules that apply in Dover
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
What should I budget for a pitched roof extension in Dover?
Prices below are for Dover, using the South East England factor of ×1.12. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Dover: £2,070 to £3,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £24,500 – £29,000 | £28,500 – £37,000 | £36,500 – £47,500 |
| 4 m × 5 m 20 m² | £41,000 – £48,500 | £48,000 – £62,000 | £61,500 – £78,500 |
| 5 m × 6 m 30 m² | £62,000 – £72,500 | £72,000 – £92,500 | £92,000 – £118,000 |
For a figure based on your own dimensions, use our guide-price tool.
What is included
- Lead or proprietary flashings to the main wall
- Vaulted ceilings or flat ceilings with storage above
- Insulation to current building regulations
- Roof windows positioned for light and ventilation
- Roof design matched to the existing pitch and tiles
Matching tiles is harder than it sounds. We source reclaimed or closest-match tiles where the originals are no longer made and agree samples with you before ordering.
Working in Dover
Across CT16, CT17, we can visit, measure and advise. We also work in nearby Folkestone (7 miles), Deal (8 miles), Canterbury (15 miles), Ramsgate (15 miles).
For homes towards East Sussex, Hastings is around 37 miles away. In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Pitched roof extension questions answered
Do I need building regulations approval in Dover?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Dover, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a pitched roof extension take to build in Dover?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Is a pitched roof better than a flat roof?
Neither is better in all cases. Pitched roofs blend with traditional houses and shed water quickly; flat roofs give more headroom and suit modern designs and lanterns.
Can I have a vaulted ceiling?
Yes. A vaulted ceiling with roof windows is one of the main reasons to choose a pitched roof. It needs insulation between and under the rafters to meet the building regulations.
Book a free site visit in Dover
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.