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Caerphilly · CF83 · Gwent

Pitched roof window installation in Caerphilly

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 Caerphilly and across Gwent, 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 £845 · Supply & fit

Guide prices

Standard window

£845 – £1,395including VAT at 20%

Centre-pivot roof window with flashing kit, tiles cut and refitted, inner lining

Larger or top-hung

£1,395 – £2,045including VAT at 20%

Bigger or top-hung windows, or two in the same roof

Electric or pair

£2,045 – £3,095including VAT at 20%

Electric or solar windows, or a matched pair with blinds

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.

Areas around Caerphilly we cover

Distance is rarely the deciding factor. A roof in Risca, 6 miles from Caerphilly, gets the same survey, the same written quote and the same fitting process as one in CF83, CF82 and NP11. What changes the price is the job itself: size of unit, roof type, access and lifting. Pontypridd, around 6 miles out, is treated the same way.

What we check on a supplied unit

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 pitched roof window 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.

What the job includes

  • Tiles or slates cut and refitted neatly around the flashing
  • Rafters trimmed where the window is wider than the gap between them
  • Underlay collar or membrane dressed and taped around the frame
  • Side slopes and neighbours — We check which slope the window is going on before you commit.
  • Head height and view — We think about how the window will be used from inside before fixing its height.

From arrival to clean-up

Protection comes before tools. Floors, furniture and stairs get covered, and the ceiling below the opening is sheeted to catch dust. Up top, the fitters confirm the opening is square and the upstand or flashing suits what the maker specifies. Fixing follows, then weather-sealing into the membrane, felt or tiles. Only once the roof is tight do they turn to the internal reveal. Time on site for a pitched roof window: one day, weather permitting.

Planning and building rules in Wales

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

Each detail you send takes a question off our list. Photos inside and out show the opening and the ceiling. Rough measurements tell us the unit size. The roof covering tells us how it will be sealed in. Access notes tell us whether a tower or scaffold is needed. A product link, if you have one, lets us check it against the opening. Your postcode, CF83 or nearby, confirms travel.

Common questions in Caerphilly

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.

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.

How long does fitting take?

Fitting a pitched roof window into an existing, correctly sized opening is often a day's work. New openings take longer, because joists or rafters need trimming, an upstand or flashing has to be built or fitted, and the inside needs finishing. Large units that need lifting gear, and days lost to rain, can stretch things further. Your written quote gives a realistic estimate for your roof.

Got a unit waiting to go in, or need one sourced? Either way, start with your Caerphilly address and a couple of photos.

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

Roof windows in Caerphilly

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

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