Lizard Peninsula · TR12
House Extensions in Gunwalloe
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 Gunwalloe on the ground is half of the extension job — Gunwalloe is a coastal village in the TR12 area, where sea exposure, views and seasonal pressure shape most building decisions, with a building stock that leans toward holiday homes and replacement dwellings.
Gunwalloe sits in Lizard Peninsula — covering TR12 from Mullion, Cury, Predannack outward.
- Conservation Area
- Cornwall AONB
- Coastal exposure zone
- ✓ One studio — design, planning and build under one roof
- ✓ Local to Lizard Peninsula — not a national franchise
- ✓ Same team on paper as on site
- ✓ Fixed-fee planning packages, no surprise invoices
Local watch-list
Local snags worth knowing before drawing a Gunwalloe extension.
Watch #1
Conservation Area material and fenestration controls in central Gunwalloe
Watch #2
AONB landscape-impact scrutiny on visible elevations
Watch #3
Coastal exposure driving fixing, render and joinery spec
Who this is for
Gunwalloe 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 Gunwalloe is its own job.
Coastal setting and landscape sensitivity mean rooflines, glazing, drainage and external materials need careful handling from the first sketch. For extension specifically, parts of Gunwalloe sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape; the surrounding landscape falls inside the Cornwall Area of Outstanding Natural Beauty, so massing, height and landscape impact carry extra weight in any planning decision; coastal salt-laden air around Gunwalloe drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure. So every Gunwalloe job runs as a TR12-specific piece of work — local policy, local fabric, local builders. Most of our extension work in Gunwalloe lands on holiday homes, with detailing that has to nod to the wider Cury 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 Gunwalloe.
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.
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 Gunwalloe 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
Gunwalloe 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 Gunwalloe specifically, we'd start by checking the Conservation Area boundary 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.
- 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.
Gunwalloe is part of Mullion
Gunwalloe sits inside the Mullion catchment — we cover both as one extension territory.
See Extensions in Mullion →Local proof — Recent extension enquiries from Gunwalloe have clustered around holiday homes — we know the route through Cornwall Council on these.
Get a free feasibility viewOther services in Gunwalloe
Nearby places we cover
On a Gunwalloe site the success of a extension is decided in week one — by reading the constraints right, not by drawing them away.