Mid Cornwall · TR14 · Cornwall Council West
House extension costs in Camborne — what TR14 homeowners actually pay
Most Camborne cost questions land in the same bracket: a single-storey rear sits roughly £2,200–£2,800/m² built, a two-storey side runs £2,000–£2,500/m², and anything touching a stone-fronted elevation tends to add 8–12% for materials and detailing. We quote on measured drawings, not guesses. Extensions are the bread and butter of Cornish homes — adding the kitchen-diner the original layout never had, the bedroom for a growing family, or the light and views the back of the house should always have had. In Camborne, that work is shaped by the place itself — Camborne is one of the great Cornish mining towns, twinned with Redruth as the engine of the Cornish Mining World Heritage Site, with a strong terraced street pattern and surviving engine houses on its outskirts, with a building stock that leans toward post-war social housing estates and Victorian terraces.
Camborne sits in Mid Cornwall — just off the A30; with Truro the closest city; 4 miles from Redruth.
- Conservation Area
- Cornish Mining World Heritage Site
- ✓ Typical Camborne single-storey rear: £55k–£85k build cost
- ✓ Two-storey side extension: £85k–£140k build cost
- ✓ Wrap-around / L-shaped: £110k–£180k build cost
- ✓ Design + planning + building regs fee from £4,800 (fixed)
Local proof — Our Mid Cornwall workload means a Camborne extension project never has to wait for an out-of-county team to drive down.
Get a free feasibility viewLocal context
Why Camborne is its own job.
Locally, camborne sits within the World Heritage Site buffer; mining heritage features are protected and design statements need to address industrial character. Trevithick Road, Cross Street and the Conservation Area carry tighter material expectations. For extension specifically, parts of Camborne sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape; the wider area forms part of the Cornish Mining World Heritage Site, which adds a heritage assessment layer to most material changes. Which is why we scope Camborne projects parish-up, not template-down — the TR14 context shapes the design from day one. Whether the project is on post-war social housing estates in the centre or further out toward Redruth, the extension response is locally tuned.
Planning note
Most extensions in Cornwall are either permitted development or a straightforward householder application — but Conservation Area and AONB sites need a more careful design conversation upfront.
What we focus on
Extensions considerations specific to Camborne.
01
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
02
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
03
Extensions over a certain proportion of the original house trigger full Part L upgrade obligations to the existing building — worth knowing before brief is set.
04
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
Our process
How a Camborne extension project runs.
Step 1
Brief
We meet on site, talk through how you live now and what's missing from the current layout.
Step 2
Design
Two or three sketch directions with rough budgets, then refinement of the chosen route.
Step 3
Approvals
Planning or Cert of Lawfulness, then a full building regs package.
Step 4
Build
Either through your own builder with our drawings, or as a full build by our team.
Step 5
Handover
Snag, certify, hand over the keys to your new space.
Typical single-storey rear extensions run twelve to twenty weeks on site; two-storey and wraparound projects sixteen to thirty weeks.
Local fabric
Why a Mid Cornwall studio is the right fit for Camborne extension.
Building stock
Across Camborne (TR14) we work on miners' cottages, Victorian terraces, Wesleyan-era chapels and conversions, post-war social housing estates, modern development at Tuckingmill. Each stock type drives a different extension response — post-war social housing estates in particular needs careful detailing here.
Parish & policy
Camborne is its own town in Mid Cornwall, with planning history that's specific to the TR14 catchment.
Coverage
We cover TR14 from our studio, with regular extension jobs also running in Redruth. Most Camborne site visits get booked within the same week.
What does a first Camborne consultation cost?
Nothing. We come to the property, walk the site, talk through what works on a TR14 plot and follow up with a written feasibility note inside a week — no obligation either way.
Request a free visitRecent work nearby
Pool industrial-to-residential change-of-use last year hit Full Plans first time.
See more recent Mid Cornwall work →FAQs
Camborne Extensions — local questions answered.
- What's the average cost of a single-storey extension in Camborne?
- For a typical 20–30m² rear extension in Camborne (TR14) we'd expect £55k–£85k including VAT, depending on glazing spec and whether the kitchen is being reworked. Coastal exposure here pushes weather-tightness specs up, which is real money.
- Do extension costs in Camborne include planning and building regs?
- Our fixed-fee design package covers measured survey, planning drawings, building regs and a tendered cost plan. Build cost is separate and quoted from drawings — never guessed from a phone call.
- What pushes a Camborne extension over budget?
- Three things: ground conditions you didn't survey for, a planning condition that drives a material change, and "while we're at it" scope creep. We screen all three at feasibility stage so the number you start with is the number you finish on.
- How long does the whole process take?
- Allow roughly three months for design and approvals, then twelve to twenty weeks on site for a typical single-storey extension. Wraparounds and two-storey add-ons take longer, mostly through approval and groundworks. In Camborne specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- Do I need planning permission for an extension?
- Often no — single-storey rear extensions, side extensions and modest two-storey additions can sit inside permitted development on a typical detached house. Conservation Areas, AONB and Article 4 zones remove some of those rights, so we always check the address first.
- How much does an extension cost in Cornwall?
- Build costs in Cornwall typically run from around £2,200 to £3,200 per square metre for a good-quality single-storey extension, more for kitchen-grade fit-out or complex glazing. We give a realistic budget before drawings start, not after.
Camborne is the hub for these neighbourhoods
We run extensions across Camborne and the surrounding TR14 neighbourhoods — same studio, same site team.
- Praze-an-Beeble
TR14
- Crowan
TR14
Other services in Camborne
If you're scoping an extension in Camborne, the honest number depends on three things: ground conditions, finish level and how much of the existing fabric stays. We'll tell you which bracket you're in before you commit to a fee.