South Cornwall · PL23
House Extensions in Mixtow
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. A Mixtow brief starts on the street, not the screen — Mixtow is a creekside settlement in the PL23 area, with waterside homes, wooded valleys and narrow-lane access shaping the brief, with a building stock that leans toward boat sheds and waterside homes.
Mixtow sits in South Cornwall — covering PL23 from Fowey, Golant, Bodinnick outward.
- Coastal exposure zone
- ✓ Fixed-fee planning packages, no surprise invoices
- ✓ Measured-survey accuracy from day one
- ✓ One studio — design, planning and build under one roof
- ✓ Local to South Cornwall — not a national franchise
Local watch-list
What usually catches extension projects out in Mixtow.
Watch #1
Coastal exposure driving fixing, render and joinery spec
Who this is for
Mixtow 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 Mixtow 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, coastal salt-laden air around Mixtow drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure. So every Mixtow job runs as a PL23-specific piece of work — local policy, local fabric, local builders. Most of our extension work in Mixtow lands on boat sheds, with detailing that has to nod to the wider Golant 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 Mixtow.
01
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.
02
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.
03
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
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 Mixtow 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
Mixtow Extensions — local questions answered.
- 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. In Mixtow specifically, we'd start by checking the latest parish-level planning history before committing to a direction.
- 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.
Mixtow is part of Fowey
Mixtow sits inside the Fowey catchment — we cover both as one extension territory.
See Extensions in Fowey →Local proof — We typically have one or two extension jobs live in the PL23 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewOther services in Mixtow
Nearby places we cover
For Mixtow homeowners weighing up a extension, the right starting point is honest feasibility — that's what we lead with, before any drawings.