FORUM

Roofs fail slowly until the moment they fail suddenly. A slate that has slipped a fraction of an inch is not visible from the street; the lead flashing around a chimney can crack over years without any obvious symptom inside the house; a valley that is holding water for longer than it should can rot the timber beneath it while the ceiling below shows nothing. The warning signs are almost always there for months or years before the leak appears, but only if someone knows what to look for.

The single easiest check is to look at the roof from the ground with a pair of binoculars. Walk to a distance across the road where you can see the whole face of the roof, and look for any tile or slate that is out of line with its neighbours. Slipped slates are the most common early warning of a Roof repairs reaching the end of its useful life. If there is one, there are usually more that are on their way. Also look at ridges and hips for anything that is not perfectly straight, and check the pointing along ridge tiles - crumbling mortar is a sign of nail sickness or general age.

Gutters and fascias tell you more than the tiles do about how long a roof has been neglected. Vegetation growing in the guttering is not just cosmetic - it means the gutter has been full of debris for long enough that seeds have taken root, and water has been running down the fascia rather than through the drain. Peeling paint on wooden fascias, or streaking on brickwork below the guttering, are signs that the water has been going in the wrong place for a while. Fix the gutters and the underlying problem often disappears.

Chimneys are the highest-risk feature on most Bournemouth roofs. Lead flashing has a lifespan of thirty to forty years, and any chimney that has not been re-flashed in living memory is either fine or about to leak. The lead should sit flat against both the chimney and the roof, with no visible gaps and no white oxidation streaks running down the tiles below. Cracks in the render or brickwork of the stack itself let water in from a completely different direction, and the flashing cannot help with that. If the chimney has not been used for years and is no longer needed, capping it properly is often cheaper than repairing it.

Inside the loft, a torch and a clear afternoon tell you everything you need to know about the condition of a roof. Look at the underside of the tiles - you should not see daylight anywhere. Look at the felt or membrane behind the tiles - it should be intact, without tears, and not sagging heavily between rafters. Look at the timber - rafters and battens should be dry and unstained. Any dark staining, especially around chimneys and valleys, is old water damage and needs investigating. Any active dripping obviously does not need explaining.

Flat roofs are a category of their own and need a slightly different eye. The signs of a failing flat roof are ponding water that does not drain within a day of rain, blistering or bubbling of the surface, splits at the edges where it meets an upstand, and any lifting of the seams if it is a mineral felt roof. A flat roof that is on its last legs will often survive for months more with careful attention, but a full re-cover is much cheaper if it is scheduled before an actual leak than after.

The best time to check a roof, before autumn storms and winter freeze-thaw. A small repair identified in September - a slate replaced, a section of pointing renewed, a gutter cleared - is cheap and quick. The same problem left through winter can turn into interior water damage, wet insulation and rotted rafters, and the cost multiplies. Twenty minutes with binoculars once a year is one of the highest-value routines a Bournemouth homeowner can adopt.