Lizard Peninsula · TR12

Mullion loft conversion — feasibility first, drawings second

A well-designed loft conversion adds a bedroom, an en-suite and useful storage to homes that were never built with the upper floor in mind — usually inside permitted development and almost always cheaper per square metre than extending sideways. On a Mullion site, the brief always meets the place — Mullion is the largest village on the Lizard Peninsula, AONB-designated, with a fifteenth-century church, a working cove and the highest concentration of period housing on the peninsula, with a building stock that leans toward granite cottages around the church and modern AONB-sensitive replacement dwellings.

Mullion sits in Lizard Peninsula — covering TR12 from The Lizard outward.

  • Conservation Area
  • Cornwall AONB
  • Coastal exposure zone
  • Rural / open-countryside policy area
  • Plain-English feasibility before any drawings
  • 30+ years of Cornwall Council approvals
  • Conservation Area experience built into the fee
  • Cornwall Council regulars across every sub-area

Who this is for

Mullion runs the full mix — owner-occupier, holiday-let, commercial and the occasional smallholding — so we scope every loft conversion enquiry from the use-class up.

Local watch-list

The TR12 constraints that shape a loft conversion brief.

  • Watch #1

    Conservation Area material and fenestration controls in central Mullion

  • 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 proof — Our Lizard Peninsula workload means a Mullion loft conversion project never has to wait for an out-of-county team to drive down.

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FAQs

Mullion Loft Conversions — local questions answered.

Will I have enough headroom?
We need a minimum 2.2 metres ridge-to-joist before alterations to make a usable conversion straightforward. Less than that and we'd consider raising the ridge, which is a planning conversation, not a permitted development one. In Mullion specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
Can I live downstairs while it's built?
Yes — most loft conversions are built with the family staying in the house. There'll be a couple of disruptive days when the staircase comes through, but the bulk of the work is upstairs.
Do I need planning permission for a loft conversion?
Often no — most loft conversions sit inside permitted development on a typical Cornish house. Conservation Areas, AONB and properties on principal elevations need full planning, and we'll confirm at first review.
Will it add value?
An extra bedroom and bathroom typically adds noticeably more value than the build cost in most Cornish markets — but the value matters less than the daily use you'll get from the space.
How much does a loft conversion cost?
A simple Velux conversion starts around £30,000 in Cornwall; a rear dormer with en-suite typically runs £45,000 to £65,000; hip-to-gable and mansards more. Stair location and bathroom complexity drive most of the cost.

Local context

Why Mullion is its own job.

Locally, mullion Conservation Area covers the village centre; the wider parish is entirely within the AONB and includes Heritage Coast designation. Cliff-edge and coastal margin sites face the strictest controls in West Cornwall. For loft conversion specifically, parts of Mullion 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 Mullion 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. Which is why we scope Mullion projects parish-up, not template-down — the TR12 context shapes the design from day one. Whether the project is on granite cottages around the church in the centre or further out toward The Lizard, the loft conversion response is locally tuned.

Planning note

Most Cornish loft conversions are permitted development — but a Certificate of Lawfulness is worth the extra week and small fee for resale protection.

What we focus on

Loft Conversions considerations specific to Mullion.

  • 01

    Cut-roof Cornish properties are easier to convert than modern trussed roofs; the structural strategy varies completely.

  • 02

    Building regs require minimum 2.0 metre headroom over the stairs and 30-minute fire protection on the existing stair enclosure — both shape the design.

  • 03

    Permitted development volume allowances are 40 cubic metres on a terrace and 50 on a detached or semi — but rear dormers in Conservation Areas often need full planning.

  • 04

    Stairs eat space — a loft conversion lives or dies by where the new staircase lands and what it costs you on the floor below.

Our process

How a Mullion loft conversion project runs.

  1. Step 1

    Feasibility

    Roof, headroom, stair landing and structural assessment.

  2. Step 2

    Design

    Layout options that respect the staircase, headroom and bathroom positioning.

  3. Step 3

    Approvals

    Planning or permitted development confirmation, plus building regs.

  4. Step 4

    Build

    Sequenced to keep the family living downstairs throughout most of the work.

  5. Step 5

    Handover

    Finish, snag, certify, hand over the keys.

Loft conversions typically run six to eighteen weeks on site depending on type, with four to eight weeks of design and approvals beforehand.

Local fabric

Choosing a loft conversion team that actually knows TR12.

Building stock

Across Mullion (TR12) we work on granite cottages around the church, Edwardian guesthouses, 1960s coastal bungalows, modern AONB-sensitive replacement dwellings. Each stock type drives a different loft conversion response — granite cottages around the church in particular needs careful detailing here.

Parish & policy

Mullion is its own town in Lizard Peninsula, with planning history that's specific to the TR12 catchment.

Coverage

We cover TR12 from our studio, with regular loft conversion jobs also running in The Lizard, Helston. Most Mullion site visits get booked within the same week.

What does a first Mullion consultation cost?

Nothing. We come to the property, walk the site, talk through what works on a TR12 plot and follow up with a written feasibility note inside a week — no obligation either way.

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From initial feasibility to final handover, we manage loft conversion projects across Mullion with careful attention to what makes Lizard Peninsula unique.

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