Pitched roof extensions in Mitcham: design, approvals and build
A pitched roof extension in Mitcham starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in MitchamFrom £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 districtsCR4, SM4, SM5, SW16, SW17
Will the council need to approve it?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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.
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).
Local to Mitcham
Site visits are available across Mitcham (CR4, SM4, SM5, SW16, SW17, SW19). We also work in nearby Morden (1 mile), Tooting (2 miles), Wimbledon (2 miles), Streatham (2 miles).
For homes towards Surrey, Ewell is around 5 miles away. London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
What is included
- Roof windows positioned for light and ventilation
- Lead or proprietary flashings to the main wall
- Roof design matched to the existing pitch and tiles
- Vaulted ceilings or flat ceilings with storage above
Guide prices for Mitcham
These guide figures apply our London adjustment (×1.3) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Mitcham: £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.
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
We visit your Mitcham home, measure up, talk through what you want and check the planning position.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about a pitched roof extension in Mitcham
How long does a pitched roof extension take to build in Mitcham?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Will my neighbours in Mitcham be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Do I need building regulations approval in Mitcham?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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.
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.
Book a free site visit in Mitcham
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.