Wet weather repairs
Can a flat roof be repaired in bad weather?
The short answer
A flat roof can be made safe in bad weather, but it cannot be properly repaired in it. A temporary cover keeps water out while the storm passes. The lasting repair needs a dry deck, a clean surface and conditions that are safe to work in, so it waits until the weather clears.
What a roofer can and cannot do on a flat roof in rain and wind, and how to look after the house while you wait.
Making safe is a different job from repairing
Two jobs get confused here, and it helps to keep them apart. A make-safe is a temporary measure that stops more water getting in. It might be a sheet laid over the damaged area and weighted down, a sealed patch across a split, or a cleared outlet that lets a pool drain away. It is there to buy time, and it is not meant to last.
A repair is the permanent fix. It cuts out the failed section, prepares the surface and restores the covering so the roof works again. That needs a dry, calm spell. When a leak is coming into the house, we deal with it first and make the roof safe, then book the repair for the first suitable weather. A lasting result from work done in the middle of a downpour is not something to expect from any roofer, and anyone promising it is selling you something that will not hold.
Why a wet roof resists repair
Water does more than make the work unpleasant. Membranes, adhesives and resins grip a clean, dry surface, and a wet one defeats them. A patch stuck over damp felt or damp boards can look perfect on the day and peel away within weeks. Moisture trapped beneath a new covering can also stay there, working on the deck from the inside.
Safety is the second reason. A wet flat roof is slippery, and a gust that catches a sheet of membrane or a roll of felt can pull a person off balance. Working at height in those conditions puts the roofer and anyone below at risk. Waiting is therefore not laziness. A repair carried out in settled weather will outlast one forced through a gale, and the ceiling underneath cares about that more than about the date. Wind adds a further problem, since it lifts loose edges and makes tools and materials hard to control on an open roof with nothing to hold on to.
After a storm: first steps
Bognor sits on the Channel, and sea weather brings gales and driving rain. After a storm, a flat roof can show a lifted edge, a torn flashing or a membrane that has peeled back. Water entering through any of those should be dealt with promptly, but your safety comes first, so keep off a wet flat roof yourself, however tempting a quick look might be from the window of the room next door.
Work from inside. Move belongings, put a bucket under drips and take photographs of the damage. If a storm caused it, let your insurer know at the earliest opportunity, keep receipts for any emergency repair and hold on to the photographs. Both Which? and the Institution of Structural Engineers set out that order of events. Our answer on whether to call a roofer or your insurer first sets out the order of play, and the guide to flat roofs in winter covers storms and ponding in more depth.
Which jobs can wait for the weather
Most permanent flat roof work improves by waiting. Re-sealing laps, replacing a flashing, patching a split, relaying edge trims and renewing a tired fillet all depend on a dry surface. If the leak is slow and a temporary cover is holding, a short delay costs little and protects the quality of the repair.
Some work cannot wait. A roof open to the elements, a covering flapping in the wind or water coming through a ceiling near light fittings is a make-safe job at once. When you call, we tell you which category yours falls into, and the survey photographs show the reasoning. Nothing is left to guesswork, and you keep the pictures. Our number is 01243 252373, and WhatsApp and the enquiry form reach us just as well. Send a photograph of the ceiling stain if you have one. The flat roofing page explains what follows the make-safe.
Checking that a temporary fix is holding
A make-safe should be watched, not forgotten. Look at the ceiling and walls under the damaged area after the next shower. A stain that stays the same size is encouraging, while one that grows means water is still finding a way in. Keep your photographs together so before and after are easy to compare, whoever asks. Mark the edge of any stain in pencil with the date, because a ring that creeps outwards tells the story better than memory does.
Do not leave a temporary cover on for months. Sheeting can lift in wind and hold water against the surface, and it is no substitute for a covering. Once the weather settles, the permanent repair should follow, or a replacement if the roof is beyond repair. Our repair or replace guide explains how that call is made, and our answer on flat roof repair time shows what affects the schedule.
Related questions
Wet weather flat roof questions
Is it safe to cover the roof with a sheet myself?
We advise against it. Getting onto a wet roof is dangerous, and a badly fixed sheet can blow away or hold water against the surface. Control the leak from inside, photograph the damage and call a roofer. If you must act, keep both feet on the ground.
Does work done in the rain carry the same promise as a dry-day repair?
Ask before the work starts. A temporary make-safe is not a finished repair, and any promise should relate to the permanent work. Whatever a roofer says about their repair, get it on paper with its limits spelled out, so you know exactly where you stand if the weather turns again.