Most roof problems announce themselves long before they become expensive. A slipped slate, a dark patch on a bedroom ceiling, mortar crumbling from a ridge — each points to a specific failure with a specific fix.
This section explains what the common symptoms actually mean, how urgent each one is, and whether it is a repair or the first sign that a covering has reached the end of its life. Where a problem is genuinely dangerous, we say so plainly rather than dressing it up.
Roof tiles can crack through age, frost, impact, weather exposure, movement or installation problems. An isolated cracked tile is often a straightforward repair, whereas widespread cracking can indicate that the roof covering is deteriorating and needs a broader assessment.
See also: Is one missing roof tile serious? · Why do roof tiles slip?
Tiles can slip when fixings corrode or fail, battens deteriorate, tiles crack, wind uplift moves the covering or earlier installation was inadequate. If more than one tile has moved, the surrounding roof should be checked rather than simply replacing the most obvious tile.
See also: Is one missing roof tile serious?
Visible daylight may indicate displaced tiles, damaged roofing materials or gaps in the covering, although some roof constructions include legitimate ventilation openings. If light is accompanied by dampness, staining or draughts, an inspection is advisable.
Heavy moss may be worth removing where it blocks gutters, valleys or drainage channels, but the cleaning method must suit the roof covering. Aggressive pressure washing can damage some tiles and surface finishes, so removal should not be treated as a one-method-fits-all job.
See also: Is moss on my roof a problem?
