Bungalow extensions in Harrow
Thinking about a bungalow extension for your Harrow home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in HarrowFrom £34,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsHA0, HA1, HA2, HA3, HA7
Guide prices for Harrow
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 Harrow: £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.
Is a bungalow extension right for your house?
- Families wanting more space on one floor
- Homeowners planning for later life
- Bungalows on larger plots
Extensions in and around Harrow
We cover Harrow and the postcode districts HA0, HA1, HA2, HA3, HA7, HA9. The same team covers Wealdstone (1 mile), Wembley (2 miles), Pinner (2 miles), Northolt (3 miles), all within easy reach.
Just over the Hertfordshire border, Bushey is about 5 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.
Planning rules that apply in Harrow
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.
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.
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).
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Bungalow extension questions answered
Will my neighbours in Harrow 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 Harrow?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Harrow, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can I extend a bungalow without planning permission?
In England a single-storey rear extension to a bungalow follows the same permitted development limits as a house: 3 m or 4 m, or up to 6 m or 8 m through prior approval. Adding a storey always needs planning permission.
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.
Book a free site visit in Harrow
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.