Fit-onlySupply & fitReplacementsTrade fitting
Fitting teams across England, Wales, Scotland & NI · Call 0800 088 6248
RooflightInstallers.co.uk
Keynsham · BS31 · Somerset

Rooflight replacement in Keynsham

If the replacement rooflight on your roof now is misted, discoloured, cracked or letting water in, replacing it is often simpler than people expect. The old unit comes out, we inspect the kerb or frame underneath, and we decide with you whether it can be reused or needs rebuilding. Then the new one goes in, sealed to the roof covering and finished inside. We handle this kind of rooflight replacement in Keynsham and nearby, alongside new openings and fit-only work. Postcode BS31 and its neighbours are all within our cover.

Guide price from £1,095 · Supply & fit; building control notice fee extra in England and Wales

What the job costs in Keynsham

Like-for-like swap

£1,095 – £1,695including VAT at 20%

Old dome or unit removed and disposed of, new glass rooflight fitted to the existing sound kerb

New upstand and swap

£1,695 – £2,645including VAT at 20%

Old kerb taken off, new insulated upstand built, roof covering made good, new unit fitted

Opening or large unit

£2,645 – £4,545including VAT at 20%

Electric or larger replacement, including making good inside

Guide ranges for supply & fit; building control notice fee extra in England and Wales. 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.

Areas around Keynsham we cover

Our fitters come to you. For Keynsham that covers BS31, BS39 and BA1, plus nearby Kingswood and Mangotsfield. We do not keep a yard or showroom in the area, and you do not need to visit one. The survey happens at your property or, for fit-only work, from the photos you send. Dates follow fitter availability, which we confirm when you accept the quote.

Buying your own, or letting us supply

Supply and fit tends to suit people who would rather not pick a unit from a catalogue. We look at the roof, the opening and how you use the room, then put a replacement rooflight on the quote that fits all three. Fit-only suits people who already know what they want, or have one on site. We are happy with either. The difference is who stands behind what: on fit-only, the maker or retailer covers the product, and our workmanship guarantee covers the installation.

Included in the work

  • New unit bedded, fixed and sealed exactly as its maker shows
  • Kerb inspected for rot, height, level and fall once the old unit is off
  • Packers, an adaptor or a new insulated upstand where the old kerb falls short
  • Inside finishes — We check the condition of the plaster and trim around the opening from inside.
  • Energy rules for the new unit — We make sure the replacement meets the current energy limit, not just the old unit's performance.

From arrival to clean-up

Fitting days start with a look at the sky. If rain is due, the order of work changes so the roof is never left open to it. A typical day for a replacement rooflight runs like this: set up access, protect the room, open up the roof or prepare the existing kerb or frame, check sizes, fix, seal, then finish inside. On jobs that take more than a day, the opening is weather-sealed overnight. The last hour goes on tidying, waste removal and a walk-round with you.

Planning and building rules 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.

Details that speed up your quote

Start with your phone. Take a picture of the roof where the unit goes or already sits, then one from inside looking up. Measure what you can, even roughly. Tell us what the roof is covered with and how a fitter would reach it: ladder, garden access or scaffold. Bought it already? Send the link or spec. Add your full postcode, for example in BS31, and we can price it.

Common questions in Keynsham

Do you make good inside after fitting?

Yes, where the quote includes it. Internal finishing usually means lining the reveal with plasterboard, taping or skimming, and fitting trim where it meets the ceiling. Some people prefer their own plasterer or decorator to finish off, which is fine. The written quote spells out exactly where our work stops, so nobody is left guessing about who does what once the unit is in.

What upstand height and roof pitch does replacement rooflight 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.

Will my new replacement 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.

Ask for a quote for your Keynsham roof. Survey dates are offered based on fitter availability once you are happy with the price.

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

Replacements in Keynsham

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

CallGet a quote