Bungalow extensions in Portsmouth: design, approvals and build
Planning a bungalow extension in Portsmouth? 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 PortsmouthFrom £29,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsPO1, PO2, PO3, PO4, PO5

Planning and approvals in Portsmouth
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 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.
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).
Is a bungalow extension right for your house?
- Families wanting more space on one floor
- Homeowners planning for later life
- Bungalows on larger plots
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.
Extensions in and around Portsmouth
Postcode districts we cover around Portsmouth include PO1, PO2, PO3, PO4, PO5, PO12. Nearby, we also take on projects in Gosport (2 miles), Fareham (5 miles), Havant (6 miles), Waterlooville (6 miles).
Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
What should I budget for a bungalow extension in Portsmouth?
These guide figures apply our South East England adjustment (×1.12) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Portsmouth: £1,960 to £3,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £29,000 – £35,500 | £34,000 – £45,000 | £43,500 – £57,500 |
| 4 m × 6 m 24 m² | £47,000 – £56,500 | £55,000 – £71,500 | £69,500 – £91,500 |
| L-shape 35 m² | £68,500 – £82,500 | £80,000 – £104,000 | £101,500 – £133,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
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
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
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
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 bungalow extension in Portsmouth
Do you cover all of Portsmouth?
Yes. We cover Portsmouth and the surrounding parts of Hampshire. Site visits are free and there is no obligation.
Will my neighbours in Portsmouth 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 Portsmouth?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
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.
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.
Book a free site visit in Portsmouth
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.