Mid Cornwall · PL26 · Cornwall Council Mid
Extensions Roche: PL26 planning, Mid Cornwall fabric
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. What works on a PL26 plot rarely works elsewhere — Roche is a village in the heart of china clay country with the dramatic Roche Rock and St Michael's Chapel on its outskirts, a fifteenth-century parish church and a tight Conservation Area, with a building stock that leans toward modern small estate development and post-war estates.
Roche sits in Mid Cornwall — just off the A390; covering PL26 from Bugle, St Austell outward.
- Conservation Area
- Rural / open-countryside policy area
- ✓Conservation Area experience built into the fee
- ✓Cornwall Council Mid sub-area regulars
- ✓Free first site visit, no obligation
- ✓30+ years of Cornwall Council approvals
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Free Roche feasibility call
Tell us about your extension. We reply within 1 working day — no obligation.
Local proof — Recent extension enquiries from Roche have clustered around modern small estate development — we know the route through Cornwall Council on these.
Get a free feasibility viewLocal context
Why Roche is its own job.
Conservation Area covers the village core. Roche Rock SSSI and listed chapel, plus surrounding clay pits, shape most planning conversations. That sets the scene before any design work begins. For extension specifically, parts of Roche sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape; Cornwall Council's Local Plan applies tighter tests to isolated rural dwellings here, so design rationale and policy fit need to be set out clearly from the outset. It's the kind of detail that decides whether a Roche application gets approved at eight weeks or stalls in committee. The modern small estate development that dominate Roche (and continue out toward Lanivet) set the tone for any extension scheme here. Where a property sits inside a conservation area or is listed, the assessment tends to turn on materials, window detailing and how visible the change is from the street rather than floor area alone. Cornwall Council's conservation team, or the Planning Portal, is the right place to confirm what applies to a specific address. Granite and cob walls do not behave like modern cavity construction. Breathability, damp movement and structural openings all need drawing properly, and building control will want that shown rather than assumed.
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 Roche.
01
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
02
Permitted development for rear extensions runs to four metres on a detached house, three on a semi or terrace — but Article 4 areas remove this in some parishes.
03
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
04
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
Keep reading
Related PL26 pages
We cover Roche and the wider PL26 district directly. Extensions enquiries here are common enough that we know the constraints before the first visit.
Who this is for
Our footing in Mid Cornwall
- Designated-area work is routine here, so heritage and landscape statements are produced alongside the drawings rather than outsourced.
- Drawings, planning and building regulations are all produced in-house, so an extension enquiry does not get passed between firms.
- Design and build are offered from the same studio, which means the person answering your Roche questions has seen the detail built.
Planning rules change and every site is different. For the final position on your address, check with Cornwall Council as the local planning authority or the Planning Portal.
Scope
Where our work starts and stops on a PL26 project
Not every project needs every stage. On a Roche job we scope to what the site and the consent route actually require.
Construction and technical drawings
1:10 and 1:20 details for the parts of the job builders normally have to guess at.
Heritage and design statements
Written justification where designation makes the design case as important as the drawing.
Planning application drawings
Existing and proposed plans, elevations, site and block plans drawn to validation standard.
Full design and build
One contract from first sketch to handover, with the same team on paper and on site.
Building regulation drawings
Full Plans sets with sections, construction notes and coordinated structural information.
Page purpose
Drawings only, or drawings through to handover in Roche?
Both routes are open on a PL26 project, and the honest answer depends on whether you already have a builder you trust. Plenty of Roche clients take the drawings, tender them locally, then come back to us for the build if the numbers do not stack up.
- Route one: feasibility, planning and a tender-ready technical pack
- Route two: the same pack, then the build under one contract
- Either way the survey and feasibility work is identical, so the decision can wait
- Fees quoted per stage against the PL26 scope, not as one opaque figure
Our process
How a Roche 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.
Quick check
Want a straight answer on whether your Roche project is worth pursuing?
Send a few details — we'll come back within 1 working day with a plain-English view on planning risk, likely cost band and whether it's a project we'd take on.
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Get a free feasibility view
For projects in Roche and the PL26 area.
Local fabric
Why a Mid Cornwall studio is the right fit for Roche extension.
Building stock
Across Roche (PL26) we work on traditional cob and granite cottages, Victorian terraces, Edwardian houses, post-war estates, modern small estate development. Each stock type drives a different extension response — modern small estate development in particular needs careful detailing here.
Parish & policy
Roche is its own town in Mid Cornwall, with planning history that's specific to the PL26 catchment.
Coverage
We cover PL26 from our studio, with regular extension jobs also running in St Austell. Most Roche site visits get booked within the same week.
How quickly can you visit a Roche site?
Usually within the same week. Roche (PL26) is on our regular Mid Cornwall run, alongside St Austell. First visits are free and you'll get an honest feasibility view inside seven days.
Request a free visitFAQs
Roche Extensions — local questions answered.
- Will my house be liveable during the build?
- For most rear and side extensions, yes — we sequence the works so the kitchen and one bathroom stay functional until the new build is watertight and connected. In Roche specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- 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.
- 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.
- 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.
- We live in the house. Can an extension in Roche be done while we stay put?
- Usually yes for single-storey and rear work, with a temporary kitchen or bathroom arrangement agreed before the start. Whole-house remodels and roof work in Roche are often easier if you move out for a few weeks. We set that expectation at feasibility stage rather than halfway through.
- 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.
Other services in Roche
Nearby places we cover
On a Roche site the success of an extension is decided in week one — by reading the constraints right, not by drawing them away. For the final position on any address, Cornwall Council or the Planning Portal is the place to confirm it.
Talk to a Cornwall studio that knows Roche Extensions enquiries here usually start with a walk round.
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