Flat Rooflight Leaking in a Storm: What to Do Right Now
If a flat rooflight is leaking in a storm, deal with it from inside. Move what is below out of the way, catch the water in a bucket, lay towels, and if it is running near a light fitting turn that circuit off at the consumer unit. Do not go onto the roof. A wet flat roof is slippery, an old rooflight will not carry your weight, and nothing you could do up there in a gale is worth the fall. The leak will stop when the storm eases, and the real work, finding why it let go and replacing the failed detail, follows a proper survey once the roof is dry. Photograph everything while it is happening, because that evidence tells an installer more than the dry roof will.
This page is the immediate steps and what comes next. Why kerbs fail is on leaks at the rooflight kerb, and a cracked dome is on a cracked dome rooflight. The wider job is on flat roof skylight installation.
What to do right now, indoors
- Protect what is below. Move furniture, electricals and anything that matters out from under the drip.
- Catch the water. A bucket under the main drip, towels to soak the spread. If water is pooling above a plasterboard ceiling and bulging it, a small pierce with a screwdriver into the lowest point of the bulge, bucket underneath, lets it drain in a controlled way rather than bringing the whole ceiling down. Only do this if you can reach it safely from a step, not a ladder in a hurry.
- Deal with electrics. If water is near a light fitting, a downlight or a socket, turn that circuit off at the consumer unit. Water and electricity together is the one part of this that is genuinely dangerous indoors.
- Note where it comes in. Which corner, which edge, and whether it tracks with the wind direction. This is the single most useful thing for diagnosis.
Do not go onto the roof, in the storm or after it. A wet flat roof is slippery, an ageing rooflight will not carry your weight, and a brittle old dome can give way underfoot. There is nothing you can safely do up there during a storm that changes the outcome. Deal with it from inside and leave the roof to a survey with proper edge protection.
Why it leaks in a storm specifically
A rooflight that is dry in normal rain and leaks in a storm is almost always failing at the kerb, and the storm is doing something ordinary rain does not: driving water sideways and upward. Wind-driven rain climbs the vertical face of the upstand and gets behind a covering that was stopped short, or tops an upstand built too low for the exposure, or forces water under a termination that has started to lift. The leak from one direction of wind, at one corner, is the signature. It means the detail is marginal and the next big storm will do it again, which is why the answer is to rebuild the detail, not to wait and hope. The causes in full are on leaks at the rooflight kerb.
The evidence to gather
While it is leaking is the best time to record it, because the dry roof afterwards hides what happened.
- Photograph the leak inside: where it enters, which corner or edge, how fast.
- Note the wind direction during the storm. A leak that only comes with wind from the sea points at a low or failed seaward upstand face.
- Photograph the roof from a window once it is safe and light, especially any standing water, two days after the rain.
- Keep the timing: whether it started this storm or has crept up over several, which tells us whether a detail has just failed or has been marginal for a while.
What the assessment involves
Once the roof is dry, a survey establishes why it let go. We lift the unit if needed, probe the kerb, check the covering termination and the upstand height, and check the fall on all four faces, because a storm leak often sits on top of a ponding problem that weakened the detail first. On a 1980s or 1990s unit the kerb timber underneath is frequently soft, and that decides the job. Then we give you one written fixed price to put it right: rebuilding the kerb where the timber has gone, dressing the covering over the head correctly, and setting the unit on the right fixings for the exposure.
We do not offer resealing or patching. A bead of mastic over a storm leak closes the visible route for a season while the wind-driven water finds another way and the timber carries on decaying. The honest repair is to rebuild the failed detail, which is what actually stops it.
Suffolk and north Essex specifics
Storm leaks cluster on the coast, because Felixstowe, Harwich and Frinton take the wind-driven rain off the North Sea that climbs an upstand and tops a detail built to an inland specification. This is exactly why we build to 200mm upstands and mechanically terminated laps within a mile of open sea, and why a rooflight fitted there to a standard national specification is the one that leaks in the first big autumn gale. Inland, storm leaks are usually a marginal kerb detail rather than exposure, and estuarine areas like Woodbridge sit between the two. Wherever you are, the safe response in the storm is the same: stay off the roof.
Common questions
What should I do if my flat rooflight is leaking right now?
Deal with it from inside. Move things out from under the drip, catch the water in a bucket, lay towels, and turn off any circuit where water is near a light or socket. If a ceiling is bulging with trapped water, pierce the lowest point to drain it into a bucket if you can reach safely. Do not go onto the roof. Photograph the leak, then arrange a survey once it is dry.
Should I go up and cover the rooflight in the storm?
No. A wet flat roof is slippery and an ageing rooflight will not carry your weight, so climbing up in a storm risks a serious fall for no real gain. The leak eases when the storm does. The fix is a proper survey and repair once the roof is dry, done with edge protection, not an emergency climb in the rain.
Why does it only leak in bad storms?
Because a storm drives rain sideways and upward, which climbs the upstand and gets behind a covering or tops an upstand built too low, where ordinary rain runs off. It means the kerb detail is marginal, and the next big storm will do it again. The answer is to rebuild the detail to the right height and termination, not to wait for the next one.
Get it assessed once it is dry
Once the storm has passed, send us photographs of the leak and the roof, the wind direction it came with, and where the property sits. We will survey it, find why it failed, and give you one written fixed price to rebuild the detail properly. Every installation carries a 10-year workmanship guarantee, and coastal work is built to the marine specification as standard.
Request a fixed quote in Ipswich, Suffolk or north Essex.
Thinking about this job? We survey across Ipswich, Suffolk and north Essex and give you a fixed price before any work starts, with a 10-year workmanship guarantee.