Pitched roof extensions in Chislehurst: design, approvals and build
Planning a pitched roof extension in Chislehurst? 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 ChislehurstFrom £28,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsBR7
Planning and approvals in Chislehurst
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.
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).
What should I budget for a pitched roof extension in Chislehurst?
For Chislehurst we adjust our national guide rates by ×1.3, the factor we use for London. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Chislehurst: £2,400 to £4,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £28,500 – £34,000 | £33,500 – £43,000 | £42,500 – £55,000 |
| 4 m × 5 m 20 m² | £48,000 – £56,000 | £55,500 – £71,500 | £71,500 – £91,000 |
| 5 m × 6 m 30 m² | £72,000 – £84,000 | £83,500 – £107,500 | £107,000 – £136,500 |
For a figure based on your own dimensions, use our guide-price tool.
Extensions in and around Chislehurst
Across BR7, we can visit, measure and advise. The same team covers Eltham (2 miles), Orpington (3 miles), Welling (4 miles), Bexley (4 miles), all within easy reach.
Swanley, in Kent, is roughly 5 miles from Chislehurst and also on our list. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
What we take care of
- Roof design matched to the existing pitch and tiles
- Roof windows positioned for light and ventilation
- Lead or proprietary flashings to the main wall
- Vaulted ceilings or flat ceilings with storage above
From first visit to completion
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
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a pitched roof extension in Chislehurst
Do I need building regulations approval in Chislehurst?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for a pitched roof extension in Chislehurst?
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.
How long does a pitched roof extension take to build in Chislehurst?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
How much does a pitched roof extension cost?
Our guide range is about £2,400 to £4,550 per m² including VAT, a little more than a flat roof because of the roof structure and tiles.
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 Chislehurst
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.