📋 Roofing guide
Most roofing problems start small and give warning signs before they become expensive. Here is what to look for from the ground, and when to call a roofer.
The roofs we see in the worst condition are rarely ones that failed suddenly. More often, there were signs for months or years — a missing tile, some crumbling mortar, a small damp patch — that were not acted on. By the time water is coming in visibly, the damage to the roof structure and the property beneath can be significantly worse than if the problem had been caught early.
You do not need to get on a ladder to spot most of the early warning signs. Here is what to look for.
Look along the roof plane. Tiles should form a continuous, even surface. Any gap, or tile that has slipped down below the line of its neighbours, means rainwater can enter directly.
Cracks are visible on closer inspection. A cracked tile will let water through under heavy rain, particularly where the crack crosses the lap between tiles.
Stand back and sight along the roof. It should be flat and even. Any visible dip or sag suggests damaged or rotted timbers underneath — a more serious structural issue.
Look at the apex of the roof. Ridge tiles should be level and uncracked. Gaps in the mortar bedding, or cracked ridge tiles, are a common entry point for water and wind.
Some moss on a roof is normal in the UK climate. Dense growth, or vegetation taking root between tiles, indicates moisture is being retained — which accelerates deterioration of mortar and tiles.
The flaunching — the mortar around the base of chimney pots — and the pointing between bricks both weather over time. Gaps or crumbling mortar allow water ingress directly into the stack.
Not all roofing problems are immediately visible from the outside. Check your loft or roof space regularly — particularly after heavy rain or strong winds.
These can appear some distance from the actual entry point, as water travels along rafters and joists before dropping. Track back towards the roof rather than assuming the leak is directly above the stain.
On a bright day, stand in the loft and look up. Any pinpoints of light indicate gaps — missing or slipped tiles, failed ridge mortar or open joints between tiles.
Dark staining on rafters or joists, or timbers that feel damp to the touch, indicate sustained moisture exposure. This is a more serious sign and warrants a professional inspection.
The breathable membrane beneath the tiles should be continuous and intact. If you can see tears or areas where it has pulled away from the battens, it is no longer providing its secondary waterproofing function.
Lead flashings — at the junction between the roof and a chimney, dormer, parapet wall or abutment — are one of the most common points of failure on older roofs. Lead weathers and eventually cracks; the mortar that holds it into the brickwork deteriorates; and joints that were dressed correctly 30 years ago can open up over time.
Flashing failures rarely announce themselves dramatically. More often there is a slow ingress of water on one side of a chimney or above a dormer, appearing as intermittent damp that puzzles the homeowner. If you have a recurring damp patch in a localised area, failed flashings are one of the first things a roofer should check.
Any visible missing or broken tiles should be attended to promptly — not because one tile necessarily causes an immediate problem, but because the exposed underfelt beneath it will deteriorate quickly in UV and wet weather, and what was a £150 repair can become significantly more expensive if left.
Any damp inside the property that you cannot explain from another source should be investigated by a roofer. Do not wait for the stain to grow before acting.
If your roof is over 30 years old and has not been inspected recently, an inspection is worthwhile even without specific symptoms. Many roofing problems are far cheaper to address when caught in the early stages.
We carry out free surveys with no obligation. If we find nothing of concern, we will tell you. If we find issues, we will explain them clearly and quote for any work that is needed.
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