West Cornwall · TR18
Extensions Newlyn: TR18 planning, West 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 TR18 plot rarely works elsewhere — Newlyn is the largest fishing port in England by value of catch, immediately south of Penzance, with the Newlyn School artistic legacy still visible in studios and galleries above the harbour, with a building stock that leans toward Victorian villas on Paul Hill and granite terraces above the harbour.
Newlyn sits in West Cornwall — covering TR18 from Penzance, Mousehole outward.
- Conservation Area
- Coastal exposure zone
- ✓ Plain-English feasibility before any drawings
- ✓ Conservation Area experience built into the fee
- ✓ Free first site visit, no obligation
- ✓ One studio — design, planning and build under one roof
Who this is for
Newlyn 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 watch-list
Common Newlyn pitfalls we plan around.
Watch #1
Conservation Area material and fenestration controls in central Newlyn
Watch #2
Coastal exposure driving fixing, render and joinery spec
Local proof — We typically have one or two extension jobs live in the TR18 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewFAQs
Newlyn Extensions — local questions answered.
- 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. In Newlyn specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- 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.
- 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.
Local context
Why Newlyn is its own job.
The Newlyn Conservation Area covers the harbour, Fore Street and the steep granite-cottage lanes above. Working-port character means industrial and maritime uses sit cheek by jowl with residential — material and overlooking arguments are common. That sets the scene before any design work begins. For extension specifically, parts of Newlyn sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape; coastal salt-laden air around Newlyn drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure. It's the kind of detail that decides whether a Newlyn application gets approved at eight weeks or stalls in committee. The Victorian villas on Paul Hill that dominate Newlyn (and continue out toward Penzance) 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 Newlyn.
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
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
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 Newlyn 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 Newlyn homeowners pick a local studio for extension.
Building stock
Across Newlyn (TR18) we work on fishermen's cottages, granite terraces above the harbour, Victorian villas on Paul Hill, 1960s estate housing, modern conversions of net-lofts and chapels. Each stock type drives a different extension response — Victorian villas on Paul Hill in particular needs careful detailing here.
Parish & policy
Newlyn is its own town in West Cornwall, with planning history that's specific to the TR18 catchment.
Coverage
We cover TR18 from our studio, with regular extension jobs also running in Penzance, Mousehole. Most Newlyn site visits get booked within the same week.
How quickly can you visit a Newlyn site?
Usually within the same week. Newlyn (TR18) is on our regular West Cornwall run, alongside Penzance, Mousehole. First visits are free and you'll get an honest feasibility view inside seven days.
Request a free visitNewlyn is the hub for these neighbourhoods
We run extensions across Newlyn and the surrounding TR18 neighbourhoods — same studio, same site team.
- Mousehole
TR19
Other services in Newlyn
Designing a extension in Newlyn is as much about reading the parish as reading the brief; we do both, and the planning outcomes follow.