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 Wiltshire?
In Wiltshire, a barn conversion typically costs £1,850–£3,050 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 £277,500–£457,500. Prices in the South West sit near the national average for this kind of work, and the range for Wiltshire reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (105 m²) | £194,000–£320,000 |
| Typical project (150 m²) | £277,500–£457,500 |
| Larger project (210 m²) | £388,500–£640,500 |
| Rate per m² | £1,850–£3,050 |
What moves the price most:
- Condition of the existing structure
- Services and drainage
- Glazing and finishes
- Access to the site
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 Wiltshire?
Approvals for a barn conversion in Wiltshire follow the rules for 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
The work we manage on a barn conversion:
- New roof covering where needed
- Planning or prior approval application
- Ecology and bat survey coordination
- Structural survey and feasibility
- Building control completion
- Services, drainage and septic or treatment plant
How long does it take?
Build time is typically 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 Wiltshire
The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.
Towns we cover in Wiltshire include Swindon, Salisbury, Trowbridge, Chippenham and Melksham.
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
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about barn conversions in Wiltshire
Who approves a barn conversion in Wiltshire?
Planning matters in Wiltshire go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Can I get a mortgage for a barn conversion?
Specialist self-build and conversion mortgages release money in stages. We can provide the staged costings lenders ask for.
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.
How much does a barn conversion cost in Wiltshire?
In Wiltshire, a barn conversion typically costs £1,850–£3,050 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 £277,500–£457,500. Your fixed price depends on the survey and drawings.
Do I need a bat survey?
Very often. Barns are common bat roosts, and planning authorities usually ask for an ecology survey.
