Building projects we take on in Cornwall
House extensions
- Single-storey extensions in Cornwall
- Double-storey extensions in Cornwall
- Side extensions in Cornwall
- Side return extensions in Cornwall
- Wraparound extensions in Cornwall
- Kitchen extensions in Cornwall
- Orangeries in Cornwall
- Glazed and contemporary extensions in Cornwall
- Porches in Cornwall
Loft conversions
- Dormer loft conversions in Cornwall
- Hip-to-gable loft conversions in Cornwall
- Mansard loft conversions in Cornwall
- Rooflight loft conversions in Cornwall
- Bungalow loft conversions in Cornwall
Garage, basement and barn conversions
- Garage conversions in Cornwall
- Basement conversions in Cornwall
- Barn conversions in Cornwall
- Garden annexes in Cornwall
New build homes
Renovations and structural work
Design and approvals
Guide prices in Cornwall
| Project | Guide range (inc VAT) |
|---|---|
| Single-storey extensions | £2,000–£2,950 per m² of floor area |
| Double-storey extensions | £1,700–£2,550 per m² of floor area (both floors) |
| Dormer loft conversions | £49,000–£69,500 for a typical rear dormer with en-suite |
| Garage conversions | £18,500–£30,500 for a single integral garage |
| House renovations | £900–£1,850 per m² for a medium to full renovation |
| New build homes | £2,050–£3,250 per m² of floor area (build cost) |
Prices in the South West sit near the national average for this kind of work, and the range for Cornwall reflects that.
Planning and building control in Cornwall
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.
In England a rear dormer is often permitted development if the extra roof volume is no more than 40 cubic metres on a terraced house or 50 on other houses, it does not face the road, sits no higher than the ridge and is set back from the eaves, with matching materials and obscure-glazed side windows. Balconies, front dormers and work in conservation areas need planning permission.
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.
Building in Cornwall
The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.
Questions about building in Cornwall
Do you cover all of Cornwall?
Yes. We take on projects across Cornwall, including Redruth, Falmouth, St Austell, Truro and Camborne.
How much does an extension cost in Cornwall?
A single-storey extension in Cornwall typically costs £2,000–£2,950 per m² of floor area, including VAT.
Do I need planning permission in Cornwall?
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.
Who approves building work in Cornwall?
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.