Is your roof window leaking or covered in condensation?

Record whether the water appears during rain, shortly afterwards or on dry mornings. Photograph the whole window and reveal, then the affected area. Say whether droplets can be wiped from the room-facing glass or appear somewhere you cannot reach. Do not force the sash open to take a photograph in bad weather.

VELUX Ireland notes that internal condensation can resemble a leak when warm, humid indoor air meets cooler glazing. It also recommends checking that its window is fully closed and locked. Those checks are useful context, but a dry-day observation does not rule out a separate weather-related defect.[1]

If you can operate the window safely in the normal way, follow its user instructions. Do not lean through the opening or reach outside. A short record over naturally occurring weather changes is helpful; spraying the roof with a hose is not a safe homeowner diagnostic test.

• Room-side droplets: note indoor moisture, weather and which surfaces are wet.
• Damp lining or ceiling: show the mark and say when it changes.
• Moisture between glazing layers: state that it cannot be wiped away from the room side.

These descriptions help the business decide who should attend, but none is a remote diagnosis. Avoid labelling every wet patch as rising damp or every cloudy pane as roof failure. Include older repair photographs if they show whether the same area has been affected before.

If the room was recently converted, insulated, plastered or decorated, mention the work and dates. Likewise, tell the installer if water first appeared after roof repairs or a window replacement. Provide the history without assuming that the most recent contractor necessarily caused the problem.

For its flat-roof windows, VELUX explains that roofing material and weathering around the frame can be involved when water appears internally. Its advice is to have the surrounding roof checked by the installer or roofer. Replacing the glass without establishing the entry route may therefore address the wrong scope.[1]

Ask whether the inspection includes the window, its installation details and the adjacent roof covering. Confirm who will arrange safe access and whether an access charge is separate. A roof-window service business and a roofer may cover different parts of the investigation; clarify responsibility before booking both.

The HSA roofwork code highlights the planning and competent use of access equipment. For a homeowner enquiry, ground-level and indoor photographs are enough. Leave outside clearing, flashing checks and work near fragile roof materials to a contractor with a suitable access plan.[2]

Use an existing invoice, guarantee record or safely accessible identification label to establish the manufacturer and model. A brand name alone may not identify the correct parts. Do not open a difficult window or remove trim solely to find a number; tell the business what paperwork you have instead.

State whether the window is fixed, manually opening or electrically operated, and whether it is in a sloping or flat roof. Mention blinds, remote controls or other accessories only if relevant to access or the fault. For a recent installation, contact the original installer before commissioning alterations and check the applicable warranty process.

Request a written diagnosis or findings summary before approving a repair. Ask what evidence supports the proposed work, what is excluded and how success will be checked. Separate the window repair from plastering and redecoration. Making a stain disappear does not establish that the source of moisture has been resolved.

Clarify attendance, access equipment, replacement parts, waste removal and making good in the total. If the proposed solution is replacement, ask why repair is unsuitable. Keep photographs and invoices, and agree what to do if the same symptom returns during the next spell of wet weather.

Illustrative brief: 'Opening roof window in a converted attic in Galway. Damp mark at the lower reveal noticed after rain; separate droplets sometimes appear on the inner glass. Indoor photographs and installation paperwork available. Please quote an inspection covering the window and surrounding roof details, with safe access and any repair priced after diagnosis.'

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