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 Sevenoaks?
In Sevenoaks, 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 Sevenoaks 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
- Access to the site
- Condition of the existing structure
- Planning conditions and ecology
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a barn conversion in Sevenoaks?
The approval route for Sevenoaks is set by planning law 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.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
The work we manage on a barn conversion:
- Services, drainage and septic or treatment plant
- Planning or prior approval application
- Insulation that respects the existing fabric
- Structural survey and feasibility
- Ecology and bat survey coordination
- Building control completion
How long does it take?
The build itself usually takes 6 to 12 months on site depending on condition. Before that, surveys, drawings and approvals usually take 4 to 9 months, longer if the council asks for changes.
Building in Sevenoaks
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.
Sevenoaks sits in Kent, about 14 miles west of Maidstone. We cover the whole of Sevenoaks, including postcodes TN13.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 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 Sevenoaks
What about drainage without mains sewer?
A sewage treatment plant can be installed, subject to the environmental regulator’s rules where you live.
Who approves a barn conversion in Sevenoaks?
Planning matters in Sevenoaks go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Do I need a bat survey?
Very often. Barns are common bat roosts, and planning authorities usually ask for an ecology survey.
How much does a barn conversion cost in Sevenoaks?
In Sevenoaks, 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.
How long does a barn conversion take?
Typically 6 to 12 months on site, depending on the building’s condition.