Roseland · TR2
Loft conversion timeline in St Mawes — week by week
From first site visit to occupation, a St Mawes loft conversion runs around 18–28 weeks. The variability sits in two places: whether planning is needed at all (most TR2 lofts are PD) and how complex the structural design is for the existing roof. We map both at feasibility stage. 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. St Mawes sits in Roseland, and that geography ends up in the drawings — St Mawes sits on the Roseland Peninsula opposite Falmouth across the Carrick Roads, with a Henrician castle, ferry harbour and one of the highest property value markets in Cornwall, with a building stock that leans toward modern architect-designed coastal homes and Victorian villas.
St Mawes sits in Roseland — covering TR2 from St Just in Roseland, Portscatho, Gerrans outward.
- Conservation Area
- Cornwall AONB
- Coastal exposure zone
- Rural / open-countryside policy area
- ✓ Feasibility + measured survey: 1–2 weeks
- ✓ PD / planning route confirmed: weeks 3–6
- ✓ Building regs + structural: weeks 6–10
- ✓ On-site build: 8–12 weeks
Local watch-list
Common St Mawes pitfalls we plan around.
Watch #1
Conservation Area material and fenestration controls in central St Mawes
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
Who this is for
St Mawes 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 context
Why St Mawes is its own job.
In St Mawes the planning picture is specific: conservation Area covers the seafront and harbour; AONB and Heritage Coast across the peninsula. Tight policy resistance to second-home expansion in some Roseland parishes. For loft conversion specifically, parts of St Mawes 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 St Mawes 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. That local reading is what makes a St Mawes (TR2) project different from a generic Cornwall scheme — and is the whole reason we work this way. On modern architect-designed coastal homes in particular — the kind you'll also find toward St Just in Roseland — the loft conversion brief always has to read the existing fabric first.
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 St Mawes.
01
Stairs eat space — a loft conversion lives or dies by where the new staircase lands and what it costs you on the floor below.
02
Cornish slate roofs come in a huge range of pitches — anything below a 30° pitch struggles to give usable headroom without raising the ridge.
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
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.
Our process
How a St Mawes loft conversion project runs.
Step 1
Feasibility
Roof, headroom, stair landing and structural assessment.
Step 2
Design
Layout options that respect the staircase, headroom and bathroom positioning.
Step 3
Approvals
Planning or permitted development confirmation, plus building regs.
Step 4
Build
Sequenced to keep the family living downstairs throughout most of the work.
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.
FAQs
St Mawes Loft Conversions — local questions answered.
- Do I need planning permission for a loft conversion in St Mawes?
- Usually no — most TR2 lofts qualify under permitted development. Conservation Area restrictions remove some PD rights here. Velux conversions are nearly always PD; full dormers sometimes need a Lawful Development Certificate.
- How long is the on-site build for a St Mawes loft conversion?
- 8–12 weeks on site, depending on stair access and whether you're staying in the property. Steel install and weather-tight enclosure happen in weeks 2–4; first fix and finishes fill the rest.
- Can the loft conversion run while we're living in the house?
- Yes — most St Mawes clients stay in. Dust protection at the existing landing is the main consideration. Bathroom commissioning is the only week you'll really notice.
- How long does a loft conversion take?
- Allow six to ten weeks on site for a Velux conversion, eight to fourteen weeks for a dormer, twelve to eighteen weeks for hip-to-gable. Add four to eight weeks for design and regs beforehand. In St Mawes specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- 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.
St Mawes is the hub for these neighbourhoods
We run loft conversions across St Mawes and the surrounding TR2 neighbourhoods — same studio, same site team.
Local proof — Most St Mawes homeowners come to us after a loft conversion quote elsewhere felt vague on planning — we lead with feasibility instead.
Get a free feasibility viewOther services in St Mawes
Nearby places we cover
Local neighbourhoods in St Mawes
A loft conversion in St Mawes doesn't need to take six months. With PD confirmation, parallel building regs and a tight on-site programme, most jobs occupy in under five months.