Bungalow extensions for homes in Carshalton
Our design and build teams take on bungalow extensions in Carshalton, from the first measured survey through planning and building control to the finished room.
- Guide price in CarshaltonFrom £34,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsSM1, SM2, SM3, SM4, SM5
Extensions in and around Carshalton
Site visits are available across Carshalton (SM1, SM2, SM3, SM4, SM5, SM6). We also work in nearby Wallington (1 mile), Sutton (2 miles), Mitcham (2 miles), Morden (2 miles).
For homes towards Surrey, Banstead is around 4 miles away. 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.
Do I need planning permission in Carshalton?
In England a single-storey extension to a bungalow follows the normal permitted development limits (3 m or 4 m, or 6 m and 8 m through prior approval). Adding a first floor always needs planning permission.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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.
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).
How much does a bungalow extension cost in Carshalton?
For Carshalton 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 Carshalton: £2,280 to £4,420 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £34,000 – £41,000 | £39,500 – £52,000 | £50,500 – £66,500 |
| 4 m × 6 m 24 m² | £54,500 – £66,000 | £63,500 – £83,000 | £81,000 – £106,500 |
| L-shape 35 m² | £79,500 – £96,000 | £93,000 – £121,000 | £118,000 – £155,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Included in a typical project
- Level thresholds and accessible layouts
- Roof designs that tie into the existing hipped or gable roof
- Single-storey extension options assessed first
- Planning application where needed
- Structural survey before any upward extension
Bungalow roofs are often hipped, which makes tying in an extension roof a careful job. We draw the roof junction early because it drives both the look and the cost.
How the project works
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 Carshalton 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.
Your questions about a bungalow extension in Carshalton
Will my neighbours in Carshalton 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.
How long does a bungalow extension take to build in Carshalton?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Do I need building regulations approval in Carshalton?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Is it better to extend sideways or upwards?
Sideways and rearwards is usually simpler, cheaper and keeps single-level living. Upwards saves garden but means stairs, more structure and planning permission.
How much does a bungalow extension cost?
Our guide range for single-storey work is about £2,280 to £4,420 per m² including VAT. Going upwards is priced after a structural survey.
Book a free site visit in Carshalton
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.