Rooflight leak repairs across Greater London

Guide prices in Greater London

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 Greater London

Greater London is part of our normal coverage in England. 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.

Included in the work

Inside check of stains, frame drainage channels and the reveal
Membrane splits at the upstand cut back and patched
Outside inspection of glass, frame, sealant, flashing and roof covering
Age of the rooflight — We weigh the age and condition of the unit before recommending a repair.
Leak or condensation — We work out whether the water is coming from outside or forming inside on cold glass.

Rules that apply in England

Replacing a rooflight in an English home is a controlled fitting: it has to be self-certified by a scheme-registered installer or notified to building control. We are not registered with a competent person scheme, so replacements we fit are notified with a building notice, and the new unit has to meet current energy limits. Adding a new one usually means a building regulations application, because joists or rafters are trimmed. On the planning side, most house rooflights are permitted development if they project 0.15 m or less; on a side slope the glass must be obscured and fixed unless the opening part is over 1.7 m above the floor.

Common questions in Greater London

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.

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.

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.

Rooflight leak repairs in Greater London