Bungalow extensions in Harlesden: design, approvals and build
Our design and build teams take on bungalow extensions in Harlesden, from the first measured survey through planning and building control to the finished room.
- Guide price in HarlesdenFrom £34,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsNW10

What is included
- Level thresholds and accessible layouts
- Planning application where needed
- Single-storey extension options assessed first
- Structural survey before any upward extension
- Roof designs that tie into the existing hipped or gable roof
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.
Local to Harlesden
Site visits are available across Harlesden (NW10). Nearby, we also take on projects in Willesden (1 mile), Cricklewood (2 miles), Wembley (2 miles), Acton (2 miles).
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 should I budget for a bungalow extension in Harlesden?
Labour and material costs vary across the UK, so for Harlesden we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Harlesden: £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 |
Try the guide-price tool to see a range for your own size and finish.
Will the council need to approve it?
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about a bungalow extension in Harlesden
Who do I contract with for a bungalow extension in Harlesden?
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.
Will my neighbours in Harlesden 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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Harlesden, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
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 Harlesden
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.