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Cardiff & the Vale · Wales

Rooflight leak repairs in Cardiff & the Vale

Across Cardiff & the Vale we fit leaking rooflights for homeowners, builders, roofers and commercial clients. The trade side matters: an extension company with jobs running in the three towns we list does not want to coordinate a different fitter for each. We can take the rooflight element of every site, fitted to the maker's instructions and left ready for the next trade. Domestic customers get the same fitting standard, quoted in writing before work begins.

Guide prices in Cardiff & the Vale

Diagnostic visit

£145 – £195including VAT at 20%

Roof and inside inspected, cause found, written repair price

Reseal and re-flash

£295 – £645including VAT at 20%

Failed sealant and flashing taken out, joints cleaned, resealed and taped

Upstand or membrane repair

£645 – £1,445including VAT at 20%

Rotten kerb section or roof membrane at the upstand repaired

Guide ranges. The first visit is charged and priced before booking; any repair is priced in writing before work starts. 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 Cardiff & the Vale

Cardiff & the Vale is part of our normal coverage in Wales. Fitting teams travel out to the property, so a town-centre terrace and a house down a farm track are treated alike, as long as a fitter can get the unit to the roof safely. Dates are offered according to fitter availability, and the cost of travel is already in your written quote.

What's included

  • Rotten kerb sections replaced where the timber has gone soft
  • Inside check of stains, frame drainage channels and the reveal
  • Outside inspection of glass, frame, sealant, flashing and roof covering
  • Water lying against the kerb — We check whether rainwater sits against the upstand after it stops raining.
  • Warranty and who fitted it — We ask who fitted the rooflight and when before working on it.

Rules that apply 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.

Common questions in Cardiff & the Vale

Is it condensation or a leak?

Condensation tends to appear on cold mornings, on the inner face of the glass, and runs down the frame. A leak usually follows rain or wind from a particular direction and often stains the ceiling around the opening. Blocked condensation channels can make the two look alike. Photos and a note of when it happens help us narrow it down before the visit.

Can you replace just the misted glass?

Often, yes. Misting between the panes means the sealed unit has failed, but the frame around it may be perfectly sound. Where the maker's design allows the glass to be changed, we measure the unit and fit a replacement, which costs less than a whole new rooflight. Where it does not, or the frame is also worn out, we explain why replacement is the better option.

Should I repair or replace my old leaking rooflight?

It depends on the age and condition of the unit and what has failed. A single perished seal or a blocked channel is worth repairing. A brittle, discoloured dome, a rotten kerb, or several faults at once usually make replacement the better value. After the diagnostic visit we set out both options with prices, so you can decide with the full picture in front of you.

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

Fitting in Cardiff & the Vale

Send photos of the problem first. We tell you what a visit costs before booking.

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