Skylight Repairs: How to Fix Leaks Around Roof Windows

A roof-window leak may come from its flashing, an unsuitable installation detail, blocked drainage channels, condensation or a defect higher up the roof. The source should be confirmed before the window is replaced. This guide explains the practical checks a Bromley property owner should make before requesting or approving work.

Quick answer

A roof-window leak may come from its flashing, an unsuitable installation detail, blocked drainage channels, condensation or a defect higher up the roof. The source should be confirmed before the window is replaced.

Maintaining roof windows and skylights

Use ground-level and internal checks, especially after severe weather or when the building has been unattended. Do not walk on the roof. Record changes over time so a roofer can distinguish a new defect from an old stain.

• Keep outlets and visible rainwater routes clear where this can be done safely
• Look for new staining, movement, cracks or displaced components
• Avoid pressure washing, uncontrolled scraping and coatings that could damage the system
• Arrange professional access when a close inspection is required
• Address small drainage and junction defects before prolonged water exposure affects the structure

Expected life is not an expiry date

Published lifespan figures are broad estimates, not guarantees. Installation quality, exposure, detailing, maintenance, movement and previous repairs can make two roofs of the same material perform very differently.

Match the defect to the weather mechanism

Wind can displace loose units and drive rain beneath marginal laps. Prolonged rainfall tests outlets and valleys. Temperature change moves metal, membranes and junctions. The inspection should identify which mechanism fits the evidence instead of describing weather as a catch-all cause.

• Windward edges, ridges and perimeter trims
• Outlets and overflow routes after sustained rain
• Lead and membrane movement points
• Debris collecting behind parapets or in valleys
• New marks after a specific weather event

What should be inspected?

• The window model, age and roof pitch compatibility
• Flashing kit and underfelt collar
• Slates or tiles immediately above and beside the opening
• Internal condensation and ventilation
• Insulation around the reveal
• Planning, building-control and structural requirements for a new opening

Check property controls before visible changes

Conservation status, listing, leases, freeholder requirements or shared ownership can affect who approves work and which visible materials are acceptable. These questions are separate from deciding whether the roof is technically defective.

• Planning status checked where relevant
• Lease or freeholder consent considered
• Matching visible material discussed
• Written approvals retained with the roof records

Ask how the work will be carried out safely

Homeowners do not need to design the contractor’s method, but they can ask what access is assumed, how edges and fragile areas are controlled and who supervises the work. Vague assurances are not a substitute for competent planning. The HSE roof-work guidance explains the main requirements and hazards.

Questions to ask in the quotation

• Is the water entry from rain or condensation?
• Can the flashing be repaired without replacing the window?
• Is the proposed product suitable for the roof covering and pitch?
• Who is responsible for internal making good?

Related local service

For property-specific advice, see Roof repairs in Bromley. The service page explains inspection, access and quotation arrangements.

Frequently asked questions

Can work continue in bad weather?

That depends on the task and safe system. High winds, lightning, ice or heavy rain can prevent access and may make opening the roof inappropriate.

What information should I give the roofer?

Provide the property location, roof type if known, when the symptom occurs, safe photographs, access constraints and details of previous related repairs.

Does every roofing job require scaffolding?

No single access method fits every property. Height, duration, roof geometry, public areas and the task determine what safe access and edge protection are required.

Discuss your roof with a local roofer

For an inspection and written quotation in Bromley, call 020 3886 3911 or email yourbromleyroofers@gmail.com. Describe the property, the roof area and any visible leak or damage. Photographs taken safely from ground level or inside the loft can also help.