West Cornwall · TR26 · Cornwall Council West
Loft conversion timeline in Carbis Bay — week by week
From first site visit to occupation, a Carbis Bay loft conversion runs around 18–28 weeks. The variability sits in two places: whether planning is needed at all (most TR26 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. Working in Carbis Bay means starting from the TR26 context — Carbis Bay is the residential coastal suburb of St Ives, climbing up the cliffs above one of the calmest beaches on the north coast and built largely between 1900 and 1970, with a building stock that leans toward modern coastal architect-designed homes and post-war bungalows.
Carbis Bay sits in West Cornwall — just off the A3074; with Truro the closest city; 1 miles from St Ives.
- Cornwall AONB
- Coastal exposure zone
- ✓ 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 Carbis Bay pitfalls we plan around.
Watch #1
AONB ridge-line scrutiny on hillside plots
Watch #2
St Ives Bay long-view protection
Watch #3
Sloped sites driving split-level slab design
Watch #4
Coastal exposure on north-facing facades
Who this is for
In Carbis Bay the loft conversion brief is almost always a private homeowner improving a forever home — so we lead with feasibility and long-term value, not show-home rhetoric.
Local context
Why Carbis Bay is its own job.
Two things shape a Carbis Bay application: parish character and policy. On policy — aONB designation covers the whole village; coastal views and cumulative cliffside development are weighed in most applications. Carbis Bay sits inside St Ives parish's principal residence policy area. For loft conversion 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; coastal salt-laden air around Carbis Bay drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure. Get that local reading right and the rest of the Carbis Bay programme tends to run on time. On modern coastal architect-designed homes in particular — the kind you'll also find toward Lelant — 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 Carbis Bay.
01
Cornish slate roofs come in a huge range of pitches — anything below a 30° pitch struggles to give usable headroom without raising the ridge.
02
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.
03
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.
04
Cut-roof Cornish properties are easier to convert than modern trussed roofs; the structural strategy varies completely.
Recent work nearby
Recent Carbis Bay hillside rebuild used a split-section ground slab to cut excavation in half.
See more recent West Cornwall work →Our process
How a Carbis Bay 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
Carbis Bay Loft Conversions — local questions answered.
- Do I need planning permission for a loft conversion in Carbis Bay?
- Usually no — most TR26 lofts qualify under permitted development. Article 4 catches a handful of streets, which we check first. Velux conversions are nearly always PD; full dormers sometimes need a Lawful Development Certificate.
- How long is the on-site build for a Carbis Bay 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 Carbis Bay clients stay in. Dust protection at the existing landing is the main consideration. Bathroom commissioning is the only week you'll really notice.
- 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. In Carbis Bay specifically, we'd start by checking AONB landscape sensitivity before committing to a direction.
- 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.
- 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.
Carbis Bay is the hub for these neighbourhoods
We run loft conversions across Carbis Bay and the surrounding TR26 neighbourhoods — same studio, same site team.
Local proof — Most Carbis Bay loft conversion clients we work with are second-time builders — they've seen the templated approach fail once already.
Get a free feasibility viewOther services in Carbis Bay
Nearby places we cover
A loft conversion in Carbis Bay 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.