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RooflightInstallers.co.uk
Merthyr Tydfil · CF47 · Mid Glamorgan

New rooflight in an existing roof in Merthyr Tydfil

Cut the opening. Trim the joists or rafters. Build the upstand or fit the flashing kit. Fix the unit, seal it, finish the inside. On a new opening, that is the whole job in plain terms, and each step has to be right for the next one to work. We carry out this work in Merthyr Tydfil and across Mid Glamorgan, either installing a unit you have bought or sourcing one for you. You get a written quote with the scope set out, and a written workmanship guarantee on the fitting with its terms on that quote.

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

Merthyr Tydfil 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.

Where our fitters travel

If you also own a property or a business unit in Aberdare, Rhondda or Ebbw Vale, that is no problem. We can survey and quote both, and where it suits, line the fitting days up together. Every address is reached by fitters travelling to it from their current jobs, and CF47, CF48 and CF44 sit comfortably within that pattern.

Fit-only or supply and fit

If you have bought a new rooflight yourself, we check four things before fitting. First, the delivery: open it, look for chips, cracks and bent frames, and report any damage to the seller straight away. Second, the size, measured against the builder's opening rather than the external frame. Third, the upstand height above the finished roof. Fourth, the maker's instructions, which set the fixings and sealing. Product warranty claims go to the seller and maker; our guarantee is for how it was fitted.

What we do on the day

  • Insulated upstand built square, level and to the maker's height
  • Joists or rafters trimmed with new timbers to carry the load around
  • Plasterboard reveals formed inside and left ready for skim or decoration
  • Warm or cold roof build-up — We find out whether the roof is insulated above or between the joists before designing the upstand.
  • Cables, pipes and ceiling fittings — We look into the ceiling void for anything in the way of the new opening.

How a fitting day runs

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 new 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, building control and Merthyr Tydfil

Welsh rules differ from England's in one important way: rooflights lose permitted development rights in conservation areas, National Parks, AONBs and World Heritage Sites. Elsewhere on a house, a rooflight that projects no more than 150 mm and stays below the highest part of the roof is usually fine. Building regulations still apply to new openings, replacements we fit go through a building notice because we are not scheme-registered, and the energy limit for rooflights is 2.2 W/m²K. A new Welsh Approved Document L takes effect on 4 March 2027.

Getting a price from photos

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 CF47.

Common questions in Merthyr Tydfil

Does a rooflight need building regulations approval?

In Wales a new opening generally needs building regulations approval. A replacement must be self-certified by a scheme-registered installer or covered by a building notice. We are not registered with a scheme, so replacements we fit go through 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.

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.

Questions before you commit? Send them over with your Merthyr Tydfil postcode and we will answer them plainly, with a quote alongside.

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

New openings in Merthyr Tydfil

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

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