What is a barn conversion?
A barn conversion turns an agricultural or rural building into a home while keeping its character: the brick or stone walls, roof timbers and large openings. It involves structural repair, insulation, new services and often a new floor slab.
How much does a barn conversion cost in Southsea?
In Southsea, a barn conversion typically costs £2,000–£3,350 per m² of floor area, including VAT at usually 5% (reduced rate for creating a new dwelling). For a typical 150 m² project that is roughly £300,000–£502,500. Building costs in the South East run about 12% above the UK average, and the figures for Southsea are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (105 m²) | £210,000–£352,000 |
| Typical project (150 m²) | £300,000–£502,500 |
| Larger project (210 m²) | £420,000–£703,500 |
| Rate per m² | £2,000–£3,350 |
The main things that change the cost:
- Glazing and finishes
- Condition of the existing structure
- Access to the site
- Planning conditions and ecology
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a barn conversion in Southsea?
Here is how the rules work for a barn conversion in England. In England converting an agricultural building into a home needs either full planning permission or prior approval under Class Q of the permitted development rules, which limits floor space and the number of homes. Listed barns also 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
On a typical barn conversion we handle:
- New roof covering where needed
- Structural survey and feasibility
- Ecology and bat survey coordination
- Building control completion
- Services, drainage and septic or treatment plant
- Insulation that respects the existing fabric
How long does it take?
Allow 6 to 12 months on site depending on condition. Allow time beforehand for drawings and approvals, usually 4 to 9 months.
Building in Southsea
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
If your home is in Southsea or close by in Portsmouth, Gosport and Ryde, a free home visit is the first step.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about barn conversions in Southsea
What about drainage without mains sewer?
A sewage treatment plant can be installed, subject to the environmental regulator’s rules where you live.
How long does a barn conversion take in Southsea?
Typically 6 to 12 months on site depending on condition. Design and approvals beforehand usually take 4 to 9 months.
How much does a barn conversion cost in Southsea?
In Southsea, a barn conversion typically costs £2,000–£3,350 per m² of floor area, including VAT at usually 5% (reduced rate for creating a new dwelling). A typical 150 m² project comes to roughly £300,000–£502,500. Your fixed price depends on the survey and drawings.
Do I need planning permission for a barn conversion?
Yes. A barn conversion needs planning permission or, in England only, prior approval under the agricultural permitted development rules where the building qualifies. Listed barns also need listed building consent.
Is VAT reduced on a barn conversion?
Usually yes. Converting a non-residential building into a dwelling normally qualifies for the reduced 5% VAT rate on building work. Our guide prices assume this rate.