Penwith · TR20
Design, planning and build for Morvah 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 TR20 site visit comes before a Morvah sketch, every time — Morvah is a moorland-edge hamlet in the TR20 area, where exposed weather, narrow lanes and rural character set the brief, with a building stock that leans toward converted barns and isolated houses.
Morvah sits in Penwith — covering TR20 from Pendeen, Trewellard, Lower Boscaswell outward.
- Cornwall AONB
- Rural / open-countryside policy area
- ✓ Cornwall Council regulars across every sub-area
- ✓ Local to Penwith — not a national franchise
- ✓ Same team on paper as on site
- ✓ Fixed-fee planning packages, no surprise invoices
Local proof — We typically have one or two extension jobs live in the TR20 area at any time, so the local planning officers know our drawings on sight.
Get a free feasibility viewLocal context
Why Morvah is its own job.
Cornwall Council's lens on Morvah is consistent: rural policy, landscape impact and services such as drainage are usually the key constraints, especially outside settlement boundaries. For extension specifically, 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; 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 Morvah project as a TR20-area job first — not a generic Cornwall job with a postcode bolted on. The converted barns that dominate Morvah (and continue out toward Lower Boscaswell) 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 Morvah.
01
Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.
02
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
03
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.
Our process
How a Morvah 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 Penwith studio is the right fit for Morvah extension.
Building stock
Across Morvah (TR20) we work on stone cottages, farm buildings, isolated houses, converted barns, small rural infill. Each stock type drives a different extension response — converted barns in particular needs careful detailing here.
Parish & policy
Morvah sits in the parish of Morvah, which matters for how parish-level consultation lands on a extension application.
Coverage
We cover TR20 from our studio, with regular extension jobs also running in Pendeen, Trewellard, Lower Boscaswell. Most Morvah site visits get booked within the same week.
How quickly can you visit a Morvah site?
Usually within the same week. Morvah (TR20) is on our regular Penwith run, alongside Pendeen, Trewellard, Lower Boscaswell. First visits are free and you'll get an honest feasibility view inside seven days.
Request a free visitFAQs
Morvah Extensions — local questions answered.
- 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. In Morvah specifically, we'd start by checking AONB landscape sensitivity before committing to a direction.
- 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.
- 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.
- 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.
Morvah is part of Pendeen
Morvah sits inside the Pendeen catchment — we cover both as one extension territory.
See Extensions in Pendeen →Other services in Morvah
Nearby places we cover
Most Morvah extension enquiries start with one honest conversation about what's actually allowed — and that conversation costs nothing.