North Cornwall · TR4
Design, planning and build for Goonhavern extension
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 TR4 site visit comes before a Goonhavern sketch, every time — Goonhavern is a commuter village in the TR4 area, with everyday family housing, edge-of-village plots and quick routes to its parent town, with a building stock that leans toward older cottages and modern estates.
Goonhavern sits in North Cornwall — covering TR4 from Perranporth, Bolingey, Rose outward.
- Rural / open-countryside policy area
- ✓ Cornwall Council regulars across every sub-area
- ✓ rural policy area experience built into the fee
- ✓ One studio — design, planning and build under one roof
- ✓ Local to North Cornwall — not a national franchise
Local proof — We typically have one or two extension jobs live in the TR4 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewLocal context
Why Goonhavern is its own job.
Cornwall Council's lens on Goonhavern is consistent: applications here usually turn on neighbour amenity, parking, overlooking and whether new work fits the rhythm of existing streets. 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. That's why we treat every Goonhavern project as a TR4-area job first — not a generic Cornwall job with a postcode bolted on. The older cottages that dominate Goonhavern (and continue out toward Rose) set the tone for any extension scheme here.
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 Goonhavern.
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
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
03
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.
04
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
Our process
How a Goonhavern 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.
Local fabric
Why a North Cornwall studio is the right fit for Goonhavern extension.
Building stock
Across Goonhavern (TR4) we work on post-war semis, bungalows, modern estates, older cottages, garden infill plots. Each stock type drives a different extension response — older cottages in particular needs careful detailing here.
Parish & policy
Goonhavern sits in the parish of Goonhavern, which matters for how parish-level consultation lands on a extension application.
Coverage
We cover TR4 from our studio, with regular extension jobs also running in Perranporth, Bolingey, Rose. Most Goonhavern site visits get booked within the same week.
How quickly can you visit a Goonhavern site?
Usually within the same week. Goonhavern (TR4) is on our regular North Cornwall run, alongside Perranporth, Bolingey, Rose. First visits are free and you'll get an honest feasibility view inside seven days.
Request a free visitFAQs
Goonhavern 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 Goonhavern specifically, we'd start by checking the latest parish-level planning history 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.
- 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.
- 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.
Goonhavern is part of Perranporth
Goonhavern sits inside the Perranporth catchment — we cover both as one extension territory.
See Extensions in Perranporth →Other services in Goonhavern
Nearby places we cover
Most Goonhavern extension enquiries start with one honest conversation about what's actually allowed — and that conversation costs nothing.