West Cornwall · TR18
House Extensions in Gulval
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. In Gulval, that work is shaped by the place itself — Gulval is a historic parish village just north-east of Penzance, with a fifteenth-century church, granite cottages around a sheltered green and views down to Mounts Bay, with a building stock that leans toward granite churchyard cottages and Georgian rectory-era houses.
- Conservation Area
Local context
Why Gulval is its own job.
Gulval Conservation Area covers the village core and church; close design scrutiny on materials and roof form. The parish has resisted large estate development in recent local plan rounds. For extension specifically, parts of Gulval sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape. That's why we treat every Gulval project as a TR18-area job first — not a generic Cornwall job with a postcode bolted on.
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 Gulval.
01
Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.
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
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 Gulval 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
Gulval Extensions — common questions.
- 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 Gulval specifically, we'd start by checking the Conservation Area boundary 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.
- 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.
Other services in Gulval
Nearby places we cover