A leaking roof window is frustrating, but it's rarely the glass itself letting water in, the cause is almost always somewhere around the frame or flashing. Tracking down exactly where the water is getting in is the key to fixing it properly rather than just patching over the symptom for a season or two.
The Most Common Culprits
Flashing that has aged, corroded or come loose is by far the most frequent cause, especially on older installations where the sealant has hardened and cracked over time after years of Bristol's wet and windy weather. A blocked drainage channel around the base of the window is another common issue, debris and moss can stop rainwater draining away as it should, causing it to back up and find its way inside.
Perished rubber seals around the opening sash, condensation building up on cold glass and being mistaken for a leak, and, less commonly, an installation that wasn't quite right in the first place, are the other usual suspects worth ruling out.
Getting to the Bottom of It
Because water can travel some distance before it becomes visible as a stain on the ceiling, a proper inspection from outside is usually needed to pinpoint the actual source rather than guessing at repairs. Left unaddressed, even a small leak around a roof window can lead to damp timber and lasting damage to plasterboard over time.
If you've noticed staining, dripping or a musty smell near a roof window, Brunel Roofing Bristol offers a 24-hour emergency call-out and can inspect the flashing and seals to identify the real cause before recommending an appropriate repair.
Repair or Replace
Sometimes a leak can be resolved by resealing or replacing just the flashing, which is a far smaller job than swapping the whole window. Where the window itself is old, worn out or was a poor match for the roof in the first place, replacement often works out the more sensible long-term fix.
As a rough guide only, a flashing repair tends to be a modest cost compared with a full window replacement, though actual cost depends on the extent of the damage, so an inspection is the only way to know which route makes sense for your roof.
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