Pitched roof extensions across Dartford
Our design and build teams take on pitched roof extensions in Dartford, from the first measured survey through planning and building control to the finished room.
- Guide price in DartfordFrom £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 districtsDA1, DA2, DA9

When a pitched roof extension makes sense
- Homeowners who prefer a vaulted ceiling
- Traditional, period and rural houses
- Conservation-sensitive streets
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.
Extensions in and around Dartford
Site visits are available across Dartford (DA1, DA2, DA9). Nearby, we also take on projects in Swanley (4 miles), Gravesend (7 miles), Strood (12 miles), Sevenoaks (12 miles).
The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
Pitched roof extension prices in Dartford
These guide figures apply our South East England adjustment (×1.12) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Dartford: £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 |
Try the guide-price tool to see a range for your own size and finish.
Do I need planning permission in Dartford?
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.
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.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
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 Dartford home, measure up, talk through what you want and check the planning position.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
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
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Dartford
Who do I contract with for a pitched roof extension in Dartford?
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 I need building regulations approval in Dartford?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a pitched roof extension take to build in Dartford?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
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.
How much does a pitched roof extension cost?
Our guide range is about £2,070 to £3,920 per m² including VAT, a little more than a flat roof because of the roof structure and tiles.
Book a free site visit in Dartford
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.