Rain leakage around a window: what the owner should document

Identify the window and surrounding construction

Give the window a location name such as the upstairs room facing the courtyard. Include a room photograph and a safe view showing the whole opening. Record what is visible around it: a sill, adjacent cladding, shade structure or other relevant feature. Note whether the window was recently replaced or the surrounding façade was repaired. Avoid relying on a close-up of wet paint alone, because the assessor needs to understand which opening and neighbouring details the observation concerns.

Record how the rain event unfolded

Write the date, approximate time and when water was first noticed relative to the rain. Describe the first visible location and subsequent movement only as observed. If useful information about wind direction is known, include it without guessing. Note whether the window was closed and any recent cleaning or maintenance. Do not wait in an unsafe location to obtain more evidence. A short sequence of safe images can distinguish the initial observation from water that later spread across an interior surface.

Separate visible entry from the assumed defect

Mark whether water appeared at the frame, surrounding wall, head, sill or another location, while leaving the cause open. The specialist should explain which components require inspection and whether the window, its installation or adjacent building details need separate assessment. A line of visible sealant is only one part of the information available. Ask for a finding tied to the actual assembly instead of accepting a blanket instruction to reseal every edge before the route has been investigated.

Prepare installation and repair records

Provide any available window specification, installer details, warranty documents and records of previous resealing or façade work. Ask earlier contractors which product and locations were treated, if known. Manufacturer sealant documentation is product-specific, so an unidentified tube or a general promise of exterior sealant is not an adequate repair specification. Do not scrape out material to identify it yourself. The assessor can decide whether further investigation is necessary and how it should be conducted without damaging other relevant parts.

Agree professional testing and access

Ask whether the proposed assessment requires exterior access, removal of a finish or controlled testing. Request the purpose, safeguards and scope from the qualified team before agreeing. Do not reproduce the rain with a hose or block visible openings to see whether the leak stops. Technical testing and drainage interpretation belong to the appropriate specialist. Where access involves shared property or a neighbouring unit, arrange permissions and attendance before the visit so the investigation does not end with an unverified assumption.

Specify the repair and follow the same opening

Require the quotation to identify the confirmed or proposed repair locations, materials and any affected finishes. Ask how compatibility and preparation will be checked and who accepts the completed detail. Retain before-and-after records and the professional verification method. Continue observing the same opening through the agreed follow-up, noting any recurrence without declaring a universal guarantee from one dry event. If the mark returns, provide the previous findings so the team can reassess the route and the repaired scope together.

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