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 Brentwood?
In Brentwood, a barn conversion typically costs £1,900–£3,200 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 £285,000–£480,000. The guide for Brentwood reflects typical costs in the East of England, roughly 6% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (105 m²) | £199,500–£336,000 |
| Typical project (150 m²) | £285,000–£480,000 |
| Larger project (210 m²) | £399,000–£672,000 |
| Rate per m² | £1,900–£3,200 |
The main things that change the cost:
- Glazing and finishes
- Insulation approach
- 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 Brentwood?
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:
- Services, drainage and septic or treatment plant
- Planning or prior approval application
- Structural survey and feasibility
- New roof covering where needed
- Ecology and bat survey coordination
- Building control completion
How long does it take?
Build time is typically 6 to 12 months on site depending on condition. Allow time beforehand for drawings and approvals, usually 4 to 9 months.
Building in Brentwood
Across the East of England, 1930s and post-war semis, newer estates and rural cottages all feature, each with different extension and loft options.
Brentwood sits in Essex, about 11 miles south-west of Chelmsford. We cover the whole of Brentwood, including postcodes CM14.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about barn conversions in Brentwood
How much does a barn conversion cost in Brentwood?
In Brentwood, a barn conversion typically costs £1,900–£3,200 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 £285,000–£480,000. 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.
Do you build barn conversions in Brentwood?
Yes. We build barn conversions across Brentwood, including postcodes CM14. Every project starts with a free home visit.
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.
What about drainage without mains sewer?
A sewage treatment plant can be installed, subject to the environmental regulator’s rules where you live.