Stopping water is a different job from repairing a roof
An emergency visit and a leak repair are two different purchases, and mixing them up is where most of the frustration in this work comes from. The emergency visit buys a stopped leak tonight. It does not buy a diagnosis, and it does not buy a repair that will still be there next winter.
The reason is material, not effort. Membranes weld and adhesives bond to a clean dry surface at a sensible temperature, and a roof in a storm is none of those things. So the crew works mechanically instead: patches fixed down, sheets dried in at the edges, tapes over a split, a blocked outlet opened so the water on the roof has somewhere to go. That is genuine work and it saves real money inside the building. It is still a hold.
The permanent repair is the other purchase, and it starts with finding where the water actually entered. That is set out on our leak repair page, which is about tracing and a lasting fix rather than about the first night.
What decides whether anyone goes on the roof that night
Not much on a commercial roof is safe to walk in a storm in the dark. Lightning stops work outright. Wind decides whether a sheet can be handled at all, because a loose sheet at height is a hazard to everyone below. Ice, standing water and a surface slick with rain hide the edge, the rooflights and the open detail somebody is looking for.
So the decision gets made out loud, and sometimes the answer is that nobody goes up. That is not a wasted visit. Containment inside, electrics made safe, stock moved and the damage photographed all happen anyway, and they are usually the larger part of what the night was going to save you.
What happens after the first visit
You should leave the night with three things: water stopped or contained, photographs of what was found, and a date. The paperwork should say in plain words which parts of the work are temporary, because that sentence is what protects you later with an insurer, with a warranty provider and with whoever asks why the same spot leaked twice.
The permanent repair is then booked into weather the materials can live with. If the leak has been running for a while, expect the return visit to include opening the detail and taking out wet insulation, which is work nobody can size accurately by torchlight. Our guide to roof leaks covers what the water is doing above the ceiling in the meantime.
Common questions
What should we do inside the building before you arrive?
Protect people first, then the electrics, then the stock. Almost everything else can wait, and most of it can be undone later.
- Move people and anything valuable out from under the drip
- Isolate circuits below the leak if water is near a light or a fitting
- Catch and channel the water rather than letting it run across a floor
- Photograph the drip, the stain and any damaged contents before clearing up
Then note the time it started, the weather and the wind direction. It reads like an afterthought and it is often the most valuable thing anybody does that night, because the conditions a leak shows itself in narrow the search on the roof the next day.
Is it better to call at night or wait until the morning?
Call while water is entering the building. Waiting only makes sense once the water has stopped and nothing underneath is at risk.
- Water keeps spreading sideways through the insulation while it is still coming in
- Interior damage is the part that grows fastest and costs most
- A roof that is leaking in the dark is rarely safe to search in the dark
- Some of the night work is inside, and that part is always worth doing
We will tell you plainly when there is nothing useful to do on the roof until daylight. Attending to protect the inside and returning at first light is often the right plan, and it costs less than a crew working badly in the wet by lamp.
How long does a temporary repair hold?
Long enough to get you through the weather, and not long enough to leave. Temporary work is fastened or taped rather than bonded, because nothing bonds to a wet cold roof.
- Fixings and tapes on a wet surface rely on mechanical grip alone
- Sheets lift in wind where the edges are not properly dried in
- Sun and daily movement work away at the edge of any temporary cover
- Snow and standing water shorten it further
Treat it as cover until the first dry spell, not as protection for a season. The failure to watch for is temporary work invoiced as a repair and then forgotten, until the same spot leaks again and worse, because the insulation under it has been wet the entire time.
Do we need somebody on site when you attend out of hours?
Usually yes, or at least somebody reachable. Most of the delay on a night call is getting into the building rather than getting onto the roof.
- Keys, alarm codes, hatch keys and lift access often sit with one person
- Tenant space may need an escort at night
- Somebody inside watching the drip helps place the entry point
- Permission to work at height can rest with the building manager
Agree all of this before you need it. A short note of who holds what, kept with the roof plan, takes an hour out of the worst night of the year. If the building is unmanned, say so when you call, so the access is planned rather than discovered in the rain.
Is the emergency visit money spent twice?
Partly, and that is the honest answer. The temporary materials and most of the night hours buy you a stopped leak, not the repair that follows.
- What carries forward is the diagnosis, the photographs and what we learned about access
- The temporary cover usually comes off when the permanent repair is made
- The protection inside is not wasted, it is the damage you avoided
- A leak left running until the weather improves costs more than the second visit
The way to keep the overlap small is to have the permanent repair agreed before the crew leaves the building, so nobody pays twice for the same survey and the roof is not carrying temporary work through a whole season.