Emergency roof repairs and storm damage

Everything useful in the first hours happens at ground level or in the loft. Nothing on this list involves a ladder, and that is deliberate. The Health and Safety Executive tells people not to consider going on any roof in rain, ice, frost or strong winds, and puts the wind that affects your balance at 23mph. That is a fresh breeze, not a gale, and it is the weather people step out into thinking the worst has passed.

Take the power off where the water is

Water follows joists and cables. If it is anywhere near a ceiling light, a downlighter or a ceiling rose, switch that circuit off at the consumer unit, not the wall switch. Not sure which one? Switch off the lighting circuits and use a torch.

Move things, then catch it

Get furniture, rugs and electrics out from under it. A bucket or bin underneath, with an old towel in the bottom to stop the splash, emptied before it is full. A wet carpet left down for two days usually costs more than the tiles that let the water in.

Look in the loft, standing on the joists

With a torch, and only on the joists or on boards laid across them, never between them. Look for daylight, for water running down a rafter, and for the underlay sagging with water like a hammock. Pull soaked insulation back off the wet patch, because wet mineral wool holds water against the plaster and stops it drying. A container on a board under the drip keeps the water off the ceiling altogether.

A ceiling that is bulging

If a ceiling is sagging with trapped water, keep everyone out from under it, because it can come down in one piece. If you are not comfortable piercing it at the low point with the power off and a bin underneath, shut the door and leave it. Plaster is repairable, and once the roof is sound and the ceiling has dried, we can plaster it back.

When it is not a roofing problem first

A chimney leaning out of line, a gable or parapet that has moved, or masonry loose above a path is a dangerous structure before it is a roof repair. Keep people away and ring the council's building control. Section 78 of the Building Act 1984 gives a council the power to act straight away on a dangerous building. A cable down across the garden or pulled off the wall stops everything else: do not touch it, keep people back and ring 105, the free power cut number.

If the water is clean and it keeps coming on a dry day, it may not be the roof at all. A tank, a cylinder or a pipe in the loft leaks whatever the weather. A roof leak follows the rain, and often the wind direction too.

A leak rarely comes through the ceiling where it gets into the roof. Water that passes a tile or a flashing lands on the underlay, runs down to a batten or a rafter, and follows it until it drips off. From there it can cross the top of the ceiling before it shows. So we start where the water can get in and work towards the stain, not the other way round.

• Chimneys. Aprons, step flashings, soakers, the back gutter and the flaunching round the pots.
• Valleys and abutments. Where two slopes meet, or a roof meets a wall, a lot of water funnels through a narrow detail. A blocked or undersized valley overflows in heavy rain.
• The field of the roof. Slipped, cracked or porous tiles, and nail fatigue that lets whole runs of slates slide.
• Wind driven rain. Some leaks show only when the wind blows from one direction, pushing rain up under laps and verges. When you ring, tell us which way the wind was.
• Gutters and downpipes. A blocked gutter overflowing at the back edge puts water into the wall and the soffit, and looks like a roof leak from inside.
• Condensation. Damp on the underside of the roof with no single drip is often warm air from the house condensing in a cold loft. That is a ventilation question, not a leak.

That last one matters, because a condensation problem patched as a leak comes straight back. We look for a pattern: wet on the north slope, on the nails and round the loft hatch points to condensation, one wet track from one point to rain. Our piece on what a brown stain on the ceiling means goes through how to tell. If the cause turns out to be the rainwater run and not the roof, clearing it is on our gutter cleaning page, and renewing a rotten fascia, soffit or gutter is on our fascias, soffits and guttering page.

We photograph the route the water takes at each point, so you see what we saw. That is also the evidence an insurer or a landlord asks for.

Storms that hit the UK are named jointly by the Met Office and its Irish and Dutch counterparts. A storm gets a name when it has the potential to cause disruption or damage that could bring an amber or red warning, which the Met Office explains in how storms are named. The name follows the warning, not the other way round, and a new list starts each September.

The colour of the warning tells you more than the name. In the Met Office severe weather advice, the amber impacts include some structural damage, such as slates dislodged from roofs, and the red impacts include roofs blown off. So an amber wind warning is the point where a sound roof can start losing material, and it goes at the edges first: the verge, the eaves and the ridge. Colour also reflects how likely the impact is, not only how bad it would be, so a yellow warning can still describe serious damage at lower confidence. Open the warning and read the impact text.

Before it arrives, everything useful is done on the ground. Put the bins, garden furniture, trampolines and ladders away. Look along the ridge and the verges from the lawn for anything already loose, and take a few dated photographs of the roof while it is still whole. Our two pieces on what a named storm and the warning colours mean and roof checks to do before winter, from the ground go into more detail. When one has been through, what to do in the first day after storm damage takes you through it in order.

After a big storm every roofer in the area is ringing round the same morning. We work through calls by how bad the water is and tell each caller honestly where they sit. A proper repair to a ridge, a valley or a slope is a dry weather job, which is why the temporary cover has to be done well.

Once the roof is dry, the question is whether the damage was a one off or the first sign of a roof at the end of its life. We will tell you straight, and if a repair will see you through, that is what we recommend.

When a repair is enough

• One or two tiles or slates slipped, and the ones round them are firmly fixed.
• A single section of ridge or verge lifted, with the rest bedded and sound.
• A flashing peeled back by the wind, with the lead itself in good order.
• A clean split or lifted lap on a flat roof whose deck is still firm and dry.

When the roof needs more

• Slates sliding in runs across a slope, which usually means the nails have rusted through everywhere.
• Old bitumen felt underlay that crumbles when touched, or battens that are soft, so a refix has nothing sound to fix into.
• The same area leaking again after an earlier repair.
• A flat roof whose deck is soft underfoot, or that ponds for days after rain.
• Ridge and verge mortar failing along the whole length, not in one spot.

On a pitched roof that means stripping and re-covering the slope, or the whole roof, with new underlay and battens. That is planned work on our roofing services page, not an emergency, and it can wait for the right weather once the roof is watertight. On a flat roof the deck decides it, and our piece comparing GRP, EPDM and felt covers the choice of covering. Chimney brickwork that has lost its pointing is a repointing job, and a stack that needs rebuilding sits with our bricklaying and repointing work.

Whichever it is, the quote is written and itemised. The make safe, the permanent repair, any scaffold and anything we could not see until the roof was opened each get their own line. For the things a quote should show, see what a roofing quote should include.