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RooflightInstallers.co.uk
Caernarfon · LL55 · Gwynedd & Anglesey

New rooflight in an existing roof in Caernarfon

Builders and extension firms in Caernarfon often want the rooflight stage of a project handled by a specialist fitting team. We step in once the roof deck or battens are ready, fit a new rooflight on your upstand or ours, detail it into the membrane or tiles, and leave the opening ready for the plasterer. Homeowners get exactly the same service directly. In each case the job is quoted in writing first, with any access or lifting needs spelt out. Jobs around LL55 and the neighbouring districts are welcome.

Guide price from £2,295 · Supply & fit, including structure and making good; building control or warrant fees extra

Caernarfon guide prices

Small fixed unit

£2,295 – £3,345including VAT at 20%

Opening cut, joists trimmed, upstand built, roof covering made good, plasterboard reveals ready for decoration

Medium fixed unit

£3,345 – £4,795including VAT at 20%

As the small unit, with a larger opening up to about 1 × 2 m and additional trimming

Large or opening unit

£4,795 – £7,795including VAT at 20%

Bigger structural work or an electric opening unit

Guide ranges for supply & fit, including structure and making good; building control or warrant fees extra. 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.

Fitting across Caernarfon and nearby

Distance is rarely the deciding factor. A roof in Bangor, 9 miles from Caernarfon, gets the same survey, the same written quote and the same fitting process as one in LL55, LL61 and LL56. What changes the price is the job itself: size of unit, roof type, access and lifting. Holyhead, around 19 miles out, is treated the same way.

Buying your own, or letting us supply

There are two ways to do this. Supply and fit means we source a new rooflight that suits your roof and install it, so one company answers for both the product choice and the fitting. Fit-only means you buy the unit and we install it. With fit-only, the product warranty stays with the maker or seller, and our written guarantee covers the fitting work. Both routes get the same checks on the opening, the upstand and the maker's instructions before anything is fixed.

What we do on the day

  • Rooflight fitted, sealed and checked for even clearance on every side
  • Survey of joist direction, roof build-up, ceiling void and access
  • Joists or rafters trimmed with new timbers to carry the load around
  • Which way the joists run — We check the direction and size of the joists before fixing the rooflight's position.
  • Planning for your roof — We check whether the new rooflight falls within permitted development for your house and nation.

From arrival to clean-up

Arrive and agree the plan. Sheet the floor and furniture. Set up the ladder, tower or scaffold. Check the opening, the upstand or flashing, and the unit against the paperwork. Fix and pack a new rooflight level. Seal it into the roof. Line the reveal or fit the ceiling trim. Clean the glass, clear the waste, and talk you through it. That is the shape of most fitting days, and for this type of job it usually takes two to three days.

Regulations for Caernarfon properties

Wales sets energy limits of 2.2 W/m²K for rooflights and 1.4 W/m²K for roof windows, and new rooflight openings generally need building regulations approval. Replacement units are controlled fittings; we are not registered with a competent person scheme, so ours are covered by a building notice to the council. Planning permission is needed for rooflights in conservation areas, National Parks, AONBs and World Heritage Sites. We check which applies and include the fee in your quote.

Details that speed up your quote

For fit-only work, the product details matter most: the link, the spec sheet, or a photo of the label on the box. Alongside that, send pictures of the roof and the ceiling below, approximate opening sizes, the type of roof covering, and how someone would get onto the roof. For supply and fit, the same photos and sizes do the job. Finish with your postcode, such as LL55.

Common questions in Caernarfon

Can you replace an old dome without redoing the whole roof?

Usually, yes. If the existing kerb is sound, level and tall enough, a new unit can often sit on it with a fresh seal to the roof covering. If the kerb is rotten or too low, we rebuild it and patch the covering around it rather than stripping the whole roof. This is checked at the survey and included in the written quote, so you know the full scope first.

Will my new 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.

Can you remove and dispose of the old rooflight?

Yes. Taking out the old unit is part of any replacement job, and it leaves with the rest of the waste unless you ask to keep it. Old domes, glass and frames go through proper waste routes. If removal turns up a rotten kerb or damaged decking, we show you what we have found and agree the repair with you before going any further.

Ask for a quote for your Caernarfon 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

New openings in Caernarfon

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

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