Building services in Portsmouth
House extensions
- Single-storey extensions
- Double-storey extensions
- Side extensions
- Side return extensions
- Wraparound extensions
- Kitchen extensions
- Orangeries
- Glazed and contemporary extensions
- Porches
Loft conversions
- Dormer loft conversions
- Hip-to-gable loft conversions
- Mansard loft conversions
- Rooflight loft conversions
- Bungalow loft conversions
Garage, basement and barn conversions
New build homes
Renovations and structural work
Design and approvals
Guide prices in Portsmouth
| Project | Guide range (inc VAT) |
|---|---|
| Double-storey extensions | £1,850–£2,800 per m² of floor area (both floors) |
| Kitchen extensions | £2,500–£3,800 per m² including a mid-range kitchen |
| Dormer loft conversions | £54,000–£76,000 for a typical rear dormer with en-suite |
| Garage conversions | £20,000–£33,500 for a single integral garage |
| House renovations | £1,000–£2,000 per m² for a medium to full renovation |
| Structural alterations and knock-throughs | £5,000–£10,500 for a typical knock-through with steel beam |
That range is adjusted for the South East, where domestic building work typically costs around 12% above the national average.
Planning permission in Portsmouth
In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
About building in Portsmouth
The South East has a broad mix of housing, from Victorian terraces in the towns to post-war semis and newer estates, so extension types vary street by street.
If your home is in Portsmouth or close by in Southsea, Gosport and Fareham, a free home visit is the first step. Portsmouth has a population of around 210,000.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions from homeowners in Portsmouth
Do I need planning permission for an extension in Portsmouth?
In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Do you work in Portsmouth?
Yes. We take on extensions, loft conversions, conversions, renovations and new builds across Portsmouth, including postcodes PO5.
Is the home visit free?
Yes. The first visit to discuss your project and measure up for a quote is free, with no obligation.
How much does an extension cost in Portsmouth?
A single-storey extension in Portsmouth typically costs £2,200–£3,250 per m² of floor area, and a double-storey extension £1,850–£2,800 per m² of floor area (both floors), including VAT.
How much does a loft conversion cost in Portsmouth?
A rear dormer loft conversion in Portsmouth typically costs £54,000–£76,000 for a typical rear dormer with en-suite, including VAT.