Roof window leaking: what should you do?

Start with where the water appears, and what the weather is doing.

The answer in 2 lines. Water beneath a roof window does not identify the cause on its own. Moisture on the room-facing glass may be condensation; water appearing during rain may indicate a problem with the window, surrounding roof or weatherproofing. Wipe up accessible water, check that the window closes normally and photograph where the wetness starts. Stay inside. Persistent or rain-related leakage needs professional investigation, and tenants should report it to their landlord.

Start with these observations

Move bedding and belongings away from the drip, and protect the floor where safe.
Photograph the glass, frame and surrounding ceiling before wiping accessible surfaces dry.
Check that the handle closes normally and nothing visible is trapped in the seal. Do not force it.
Record whether water appears during rain, after cold nights or following activities that produce moisture indoors.

Stop: danger

Stay inside: do not climb through the window or lean outside to clear debris or inspect flashing.
Water near electrical fittings: do not touch wet lights, switches, sockets or window controls. Keep clear and arrange a qualified electrician where equipment has become wet.
Ceiling bulging or coming away: leave the affected area and keep others out until it has been assessed.

Condensation or rainwater?

Condensation forms when moist air meets a cold surface. Droplets across the inside of the glass, particularly in cold weather, make this a possibility. Water tracking from a joint or staining the ceiling during rain suggests that the roof and window need investigating. These are clues, not a diagnosis: both problems can occur together.

Use GOV.UK's existing-home ventilation guide to review background vents and extractor use. Keep intended ventilation working, use extraction when cooking or bathing, and reduce moisture from indoor clothes drying where possible.

What you can safely do yourself

Wipe the room-facing glass and accessible frame with a soft cloth. Check visible seals for dirt or damage without dismantling them. Operate the window only as intended and close it when rain could enter.

Do not poke tools into drainage openings, apply lubricant indiscriminately or remove seals to experiment. Maintenance and replacement parts depend on the particular model. If its instructions are unavailable, ask the installer or a competent specialist to identify it before attempting adjustments. Exterior drainage channels, flashings and adjacent tiles need safe professional access.

What not to do

Smearing sealant around the outside without identifying the water route.
Assuming every wet window needs replacement.
Leaving an opening exposed to rain while trying to improve ventilation.
Painting over damp staining before the cause has been resolved and the area has dried.

What to ask a roofer or window specialist

Send photographs and your weather notes. Ask for an assessment of the window's operation, seals, surrounding flashing and nearby roof covering. Water can enter away from the visible stain, so request an explanation of the likely route and evidence supporting the proposed repair.

Ask for a written quotation that includes safe access and any interior work. If replacement is proposed, ask why repair is unsuitable. A roof inspection and a window mechanism repair may require different skills; establish who will assess each part before accepting the work.

Who should arrange and pay for repairs?

Tenants in England should notify their landlord in writing and send evidence. Follow GOV.UK's repairs guidance to check the landlord's obligations and what to do if action is not taken. Persistent condensation can also involve building defects; it should not automatically be blamed on the occupant. Housing law differs elsewhere in the UK.

If installation was recent, complain in writing to whoever contracted to do the work. Gather the quotation, receipt and photographs. Citizens Advice's home-improvement guidance explains how to seek a remedy for faulty work. Any insurance payment depends on the policy and established cause.

Good to know

Keep a record of recurring wetness even if it dries between episodes.
Ventilation can reduce condensation, but it cannot repair defective weatherproofing.
A repair should address the cause as well as damaged plaster, decoration or timber.

Illustrative example: a tenant in Sheffield notices droplets on the bedroom roof window after cold nights. She photographs them, checks the accessible ventilation and reports the recurring moisture to her landlord. When a separate stain appears during rain, she sends an update so that the inspection considers both condensation and rain penetration.

A made-up story, for illustration.

Bobby

Sources, verification, confidence

Verified on 5 November 2026, for England. Confidence: high for ventilation principles, avoiding unsafe roof access and consumer repair routes; medium for distinguishing causes from observations. The window and roof require inspection before a diagnosis or repair specification.