West Cornwall · TR27
Extensions that reads Canonstown properly
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. Reading Canonstown on the ground is half of the extension job — Canonstown is a commuter village in the TR27 area, with everyday family housing, edge-of-village plots and quick routes to its parent town, with a building stock that leans toward post-war semis and modern estates.
Canonstown sits in West Cornwall — covering TR27 from Hayle, Angarrack, Phillack outward.
- Cornish Mining World Heritage Site
- ✓ Local to West Cornwall — not a national franchise
- ✓ Same team on paper as on site
- ✓ Fixed-fee planning packages, no surprise invoices
- ✓ Measured-survey accuracy from day one
Local watch-list
The TR27 constraints that shape a extension brief.
Watch #1
World Heritage Site assessment on changes visible in the mining landscape
Who this is for
Canonstown runs the full mix — owner-occupier, holiday-let, commercial and the occasional smallholding — so we scope every extension enquiry from the use-class up.
Local context
Why Canonstown is its own job.
Around Canonstown (TR27), applications here usually turn on neighbour amenity, parking, overlooking and whether new work fits the rhythm of existing streets. For extension specifically, the wider area forms part of the Cornish Mining World Heritage Site, which adds a heritage assessment layer to most material changes. Reading Canonstown properly up front saves more time than any drawing tool ever will. Most of our extension work in Canonstown lands on post-war semis, with detailing that has to nod to the wider Angarrack streetscape.
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 Canonstown.
01
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
02
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
03
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
04
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.
Our process
How a Canonstown 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.
FAQs
Canonstown Extensions — local questions answered.
- Can you handle the build as well as the design?
- Yes — that's the whole point of the studio. One contract, one point of contact, no finger-pointing between architect and builder when something needs a decision on site. In Canonstown specifically, we'd start by checking the latest parish-level planning history before committing to a direction.
- What about the Party Wall Act?
- If you share a wall with a neighbour or build close to a boundary, the Act applies. We flag it early, recommend a surveyor and keep the programme aligned with the notice period.
- 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.
- 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 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.
Canonstown is part of Hayle
Canonstown sits inside the Hayle catchment — we cover both as one extension territory.
See Extensions in Hayle →Local proof — We typically have one or two extension jobs live in the TR27 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewOther services in Canonstown
Nearby places we cover
On a Canonstown site the success of a extension is decided in week one — by reading the constraints right, not by drawing them away.