North Cornwall · PL35
One studio for extension in Boscastle
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. Boscastle sits in North Cornwall, and that geography ends up in the drawings — Boscastle is a National Trust harbour village on the north coast — famously rebuilt after the 2004 flood — with a tightly controlled Conservation Area and AONB across its dramatic valley setting, with a building stock that leans toward modern carefully detailed coastal homes and Victorian terraces above the valley.
Boscastle sits in North Cornwall — covering PL35 from Tintagel outward.
- Conservation Area
- Cornwall AONB
- Coastal exposure zone
- Rural / open-countryside policy area
- ✓ Measured-survey accuracy from day one
- ✓ One studio — design, planning and build under one roof
- ✓ Same team on paper as on site
- ✓ Fixed-fee planning packages, no surprise invoices
Our process
How a Boscastle 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 proof — Most Boscastle homeowners come to us after a extension quote elsewhere felt vague on planning — we lead with feasibility instead.
Get a free feasibility viewWhat we focus on
Extensions considerations specific to Boscastle.
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
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
04
Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.
Local context
Why Boscastle is its own job.
Two things shape a Boscastle application: parish character and policy. On policy — conservation Area, AONB and a Flood Zone 3 designation across much of the harbour valley. Post-flood reconstruction set high design and material standards that continue to apply. For extension specifically, parts of Boscastle 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 Boscastle drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure; 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. Get that local reading right and the rest of the Boscastle programme tends to run on time. On modern carefully detailed coastal homes in particular — the kind you'll also find toward Tintagel — the extension brief always has to read the existing fabric first.
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.
Local watch-list
What usually catches extension projects out in Boscastle.
Watch #1
Conservation Area material and fenestration controls in central Boscastle
Watch #2
AONB landscape-impact scrutiny on visible elevations
Watch #3
Coastal exposure driving fixing, render and joinery spec
Watch #4
Tighter Local Plan tests on isolated rural dwellings
Local fabric
Boscastle extensions — the local-studio difference.
Building stock
Across Boscastle (PL35) we work on slate harbourside cottages, Victorian terraces above the valley, post-2004 replacement dwellings, modern carefully detailed coastal homes. Each stock type drives a different extension response — modern carefully detailed coastal homes in particular needs careful detailing here.
Parish & policy
Boscastle is its own town in North Cornwall, with planning history that's specific to the PL35 catchment.
Coverage
We cover PL35 from our studio, with regular extension jobs also running in Tintagel. Most Boscastle site visits get booked within the same week.
Can you handle both planning and build in Boscastle?
Yes — design, planning, building regs and full construction run under one roof. For clients with an existing Boscastle builder we can stop at a tender-ready Full Plans pack instead.
Request a free visitWho this is for
Boscastle runs the full mix — owner-occupier, holiday-let, commercial and the occasional smallholding — so we scope every extension enquiry from the use-class up.
FAQs
Boscastle Extensions — local questions answered.
- How much does an extension cost in Boscastle?
- 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. In Boscastle specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- 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.
- 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 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.
Other services in Boscastle
Nearby places we cover
Every Boscastle extension we work on is treated as a PL35 job in its own right — local fabric, local policy, local builders.