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RooflightInstallers.co.uk
New Cross · SE14 · Greater London

Rooflight leak repairs in New Cross

Misting between the panes means the seal on the glass unit has gone. No amount of wiping will clear it, but the frame may be perfectly sound. Where the maker's design allows, rooflight leak repairs in New Cross can mean changing just the sealed unit rather than the whole rooflight. Other faults look similar from below: condensation on the inner face, or a slow leak at a perished seal. A charged diagnostic visit, priced before you book, tells you which one you have.

Guide price from £145 · Charged visit, then repair priced before any work

Guide prices

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.

Is your address covered?

Fitters travel to the job, so the address is what counts. In New Cross that means postcode districts SE14, SE8 and SE4, and the same teams can just as easily take on work in Brockley, about 1 mile away, or Greenwich at roughly 1 mile. Survey and fitting dates are offered according to fitter availability, and travel is built into the quote rather than added later.

On the day, we cover

  • Rotten kerb sections replaced where the timber has gone soft
  • Membrane splits at the upstand cut back and patched
  • Lifted flashing or tape removed and renewed
  • Age of the rooflight — We weigh the age and condition of the unit before recommending a repair.
  • Water lying against the kerb — We check whether rainwater sits against the upstand after it stops raining.

How a repair visit goes

A repair visit starts outside. The fitter looks at the roof around the unit for ponding, split membrane, loose flashing and failed sealant, then moves inside to check stains, the frame and the condensation channels. Where it helps, a controlled water test narrows down the entry point. Before leaving, they explain what they found and whether a small fix can be done within the agreed visit, or needs a separate written quote.

Regulations for New Cross properties

England's rules in short: permitted development usually covers a rooflight on a house roof provided it doesn't stick out more than 0.15 m or rise above the ridge, though a listed building always needs consent and some streets have Article 4 directions. Building regulations apply to new openings, and replacements go through building control; as we are not registered with a competent person scheme, we use a building notice and show the fee on the quote. The energy limit for rooflights in existing homes is 2.2 W/m²K, and the 2026 Approved Document L, in force from 24 March 2027, keeps that figure.

What to send us

Tell us where the water appears, how long it has been happening and what the weather was doing when it started. A couple of photos from inside and outside, plus the postcode, let us price the visit before you book and plan what the fitter brings.

Common questions in New Cross

Why is my rooflight leaking?

The usual causes are sealant that has cracked or pulled away, flashing or membrane that has perished at the edges, condensation channels blocked with dirt, water ponding against the kerb, or a seal failing on the glass unit. Sometimes the water is coming in elsewhere and running along to the rooflight. A diagnostic visit finds the real source before anyone starts applying sealant.

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.

Do you charge for a leak investigation in New Cross?

Yes. Tracing a leak properly takes time on the roof, a close look at the frame and sometimes a water test, so the visit is charged. We confirm the price before you book, so there are no surprises. If a repair is needed beyond what can be done during the visit, it is quoted separately in writing and you decide whether to go ahead.

Got a leak or a misted unit in New Cross? Send photos first and we will tell you what the visit costs before booking.

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

Leak repairs in New Cross

Send photos of the problem and we will tell you what a visit costs before booking.

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