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RooflightInstallers.co.uk
Cornwall · England

Walk-on rooflight installation in Cornwall

Across Cornwall we fit walk-on rooflights for homeowners, builders, roofers and commercial clients. The trade side matters: an extension company with jobs running in several of the 9 towns we list does not want to coordinate a different fitter for each. We can take the rooflight element of every site, fitted to the maker's instructions and left ready for the next trade. Domestic customers get the same fitting standard, quoted in writing before work begins.

Guide prices in Cornwall

Up to 1 m²

£3,345 – £4,545including VAT at 20%

Laminated walk-on unit with anti-slip finish, fitted level with the terrace

Up to 2 m²

£4,545 – £7,195including VAT at 20%

Larger walk-on glazing

Large or bespoke

£7,195 – £11,995including VAT at 20%

Big panes, structural calculations, lifting gear

Guide ranges for supply & fit. Your price is fixed in a written quote after we have seen photos or surveyed. Scaffold, access towers or a crane are priced separately if the job needs them, and building control fees, where a job needs them, are shown as their own line.

Towns we list in Cornwall

From the larger towns to the smaller places in between, we take on rooflight fitting across Cornwall. The process is the same for a terrace, a farmhouse extension or an industrial unit: details first, written quote second, fitting day third. Remote and island addresses in England, where they arise, are covered by arrangement, and we tell you that before quoting.

The Isles of Scilly are covered by arrangement, with travel priced into the quote before you commit.

What we do on the day

  • Engineer's calculations and the unit's loading data checked together
  • Perimeter joints sealed and the waterproofing lapped as the maker shows
  • Lifting plan for the unit, including people or gear for the day
  • Structural calculations — We need structural calculations for the glass and its support before a walk-on job goes ahead.
  • Units tested to old standards — We check which standard the walk-on unit has been tested to.

Rules that apply in England

In England, a new rooflight opening generally needs building regulations approval because the roof structure is altered and the glazing must meet energy rules: 2.2 W/m²K for a rooflight in an existing home, or 1.4 W/m²K (or WER Band B) for a roof window. Planning is often not needed on a house: permitted development covers rooflights that stand no more than 0.15 m proud of the roof slope and sit below the highest part of the roof. Flats, listed buildings and areas with an Article 4 direction are different, so we check your address first.

Common questions in Cornwall

Will my new walk-on rooflight leak?

A correctly fitted unit should not. Leaks usually trace back to the detail around the frame: an upstand that is too low, a membrane or flashing that is not dressed properly, sealant applied to a damp surface, or water ponding against the kerb. We fit to the maker's instructions and check each of those points. The fitting carries a written workmanship guarantee, with its terms set out on your quote.

Does a rooflight need building regulations approval?

A new opening usually needs building regulations approval. A replacement is a controlled fitting: it must be self-certified by an installer registered with a competent person scheme or notified to building control. We are not registered with a scheme, so replacements we fit are notified to building control with a building notice, and the council's fee is shown on your quote.

Can you fit a rooflight in winter or when it is raining?

Yes, within limits. Cold is less of a problem than wet, because membranes, primers and sealants need a dry surface to bond. We plan fitting days around the forecast and may move a date if heavy rain is due. If the roof has to be opened up, it is not left overnight without a temporary weather seal, so the room below stays dry while the work is finished.

Rear extension at dusk with lit rooflights and a roof lantern
Ready when you are

Fitting in Cornwall

Send photos and rough sizes, or ask for a survey visit for install work. You get one fixed written price before anything starts.

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