Roof lantern installation across Cornwall

Guide prices in Cornwall

About 1 × 2 m

£3,095 – £4,545including VAT at 20%

Aluminium lantern, double glazed, fitted and glazed on a ready upstand

About 1.5 × 3 m

£4,545 – £7,195including VAT at 20%

Mid-size lantern, solar-control glass options

2 × 4 m and over

£7,195 – £11,395including VAT at 20%

Large lanterns, lifting gear on the day

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

Coverage in Cornwall works by postcode, not by distance from an office. Give us the full postcode and we will confirm whether it is standard cover, as it is for most of England, or one of the few remote and island areas handled by arrangement. Either way, you get a written quote before any work is booked, with travel included in the price.

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

What's included

Glass cleaned and packaging cleared from the roof
Glass lifted and laid into the frame by hand or with gear
Frame assembled on the kerb in the maker's set order
Upstand size and tolerance — We check the kerb against the lantern maker's figures before the kit is opened.
Level, not to a fall — We set or check the kerb level unless your lantern's maker says otherwise.

Rules that apply in England

England's rules in short: permitted development usually covers a rooflight on a house roof provided it doesn't stick out more than 0.15 m or rise above the ridge, though a listed building always needs consent and some streets have Article 4 directions. Building regulations apply to new openings, and replacements go through building control; as we are not registered with a competent person scheme, we use a building notice and show the fee on the quote. The energy limit for rooflights in existing homes is 2.2 W/m²K, and the 2026 Approved Document L, in force from 24 March 2027, keeps that figure.

Common questions in Cornwall

What if my roof opening is the wrong size for the roof lantern?

We find out before the fitting day, not on it. If the opening is slightly out, it can usually be adjusted by trimming or by packing out the upstand. If it is a long way off, the choice is between altering the opening and changing the unit. Bear in mind that rooflights are often sold by builder's opening size rather than external size, so check which one your measurement refers to.

What upstand height and roof pitch does roof lantern fitting need?

It depends on the product. Manufacturers usually specify a minimum upstand height above the finished roof surface, and a minimum pitch on the glass so rain runs off. We follow the maker's figures for your unit rather than a rule of thumb. If your existing kerb or roof falls short, we explain the options, such as raising the upstand or choosing a unit with built-in pitch.

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.

Roof lantern installation in Cornwall