East Cornwall · PL11
House Extensions in Polbathic
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 Polbathic on the ground is half of the extension job — Polbathic is a creekside settlement in the PL11 area, with waterside homes, wooded valleys and narrow-lane access shaping the brief, with a building stock that leans toward creekside cottages and boat sheds.
Polbathic sits in East Cornwall — covering PL11 from Torpoint, Millbrook, Antony outward.
- Rural / open-countryside policy area
- ✓ Local to East 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
Polbathic-specific issues we screen on the first visit.
Watch #1
Tighter Local Plan tests on isolated rural dwellings
Who this is for
Polbathic 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 Polbathic is its own job.
Creekside ecology, flood risk, trees and views across the water often matter as much as the building form itself. For extension specifically, 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. So every Polbathic job runs as a PL11-specific piece of work — local policy, local fabric, local builders. Most of our extension work in Polbathic lands on creekside cottages, with detailing that has to nod to the wider Millbrook 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 Polbathic.
01
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
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.
Our process
How a Polbathic 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
Polbathic 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 Polbathic 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.
- 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.
- 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.
Polbathic is part of Torpoint
Polbathic sits inside the Torpoint catchment — we cover both as one extension territory.
See Extensions in Torpoint →Local proof — We typically have one or two extension jobs live in the PL11 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewOther services in Polbathic
Nearby places we cover
On a Polbathic site the success of a extension is decided in week one — by reading the constraints right, not by drawing them away.