South Cornwall · TR11 · Cornwall Council Central

Extensions for Falmouth (TR11)

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. The way we approach extension in Falmouth starts with a measured walk-round — Falmouth is a deep-water harbour town built around one of the world's largest natural harbours, with a thriving art college, Maritime Museum and a Victorian and Edwardian seafront, with a building stock that leans toward post-war suburbs at Trescobeas and Georgian merchants' houses.

Falmouth sits in South Cornwall — just off the A39; with Truro the closest city; 3 miles from Mawnan Smith.

  • Conservation Area
  • Cornwall AONB
  • Coastal exposure zone
  • Fixed-fee planning packages, no surprise invoices
  • Measured-survey accuracy from day one
  • Same team on paper as on site
  • Local to South Cornwall — not a national franchise

Our process

How a Falmouth extension project runs.

  1. Step 1

    Brief

    We meet on site, talk through how you live now and what's missing from the current layout.

  2. Step 2

    Design

    Two or three sketch directions with rough budgets, then refinement of the chosen route.

  3. Step 3

    Approvals

    Planning or Cert of Lawfulness, then a full building regs package.

  4. Step 4

    Build

    Either through your own builder with our drawings, or as a full build by our team.

  5. 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 Falmouth homeowners come to us after a extension quote elsewhere felt vague on planning — we lead with feasibility instead.

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What we focus on

Extensions considerations specific to Falmouth.

  • 01

    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.

  • 02

    Cornish granite and slate-hung walls react differently to new openings than modern brickwork — lintel choice and structural sequencing matter.

  • 03

    Wind and sea-spray exposure can drive material choices on west-facing extensions; we detail accordingly.

  • 04

    Drainage on older Cornish properties is rarely on a clean modern map; CCTV survey before design is often money well spent.

Local context

Why Falmouth is its own job.

In Falmouth the planning picture is specific: falmouth has multiple Conservation Areas — Town Centre, Greenbank, Penryn River and Pendennis — each with its own character appraisal. Article 4 directions remove some permitted development rights in the Town Centre and seafront zones; HMO licensing is a separate active policy area. For extension specifically, parts of Falmouth 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 Falmouth drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure. That local reading is what makes a Falmouth (TR11) project different from a generic Cornwall scheme — and is the whole reason we work this way. On post-war suburbs at Trescobeas in particular — the kind you'll also find toward Penryn — 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

Falmouth-specific issues we screen on the first visit.

  • Watch #1

    Marine exposure detailing on the harbour edge

  • Watch #2

    HMO licensing pressure from university lets

  • Watch #3

    Conservation Area sash-window restrictions on Arwenack and the Moor

  • Watch #4

    Steep terraced plots above Stratton Place

Local fabric

Falmouth extensions — the local-studio difference.

Building stock

Across Falmouth (TR11) we work on Georgian merchants' houses, Victorian terraces, Edwardian seafront hotels and flats, post-war suburbs at Trescobeas, modern student-converted HMOs. Each stock type drives a different extension response — post-war suburbs at Trescobeas in particular needs careful detailing here.

Parish & policy

Falmouth is its own town in South Cornwall, with planning history that's specific to the TR11 catchment.

Coverage

We cover TR11 from our studio, with regular extension jobs also running in Mawnan Smith, Penryn, Mylor Bridge. Most Falmouth site visits get booked within the same week.

Can you handle both planning and build in Falmouth?

Yes — design, planning, building regs and full construction run under one roof. For clients with an existing Falmouth builder we can stop at a tender-ready Full Plans pack instead.

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Recent work nearby

Recent HMO-to-family conversion on Killigrew Road undid 1990s subdivisions and reopened the original spine.

See more recent South Cornwall work →

Who this is for

In Falmouth the extension brief is almost always a private homeowner improving a forever home — so we lead with feasibility and long-term value, not show-home rhetoric.

FAQs

Falmouth Extensions — local questions answered.

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. In Falmouth specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
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.
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.
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.

The TR11 stretch of South Cornwall has its own rhythm; our extension work respects it, and Cornwall Council usually responds in kind.

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