Which roof problems should never be ignored?

Active ingress wets plaster, insulation and timber, and the damage extends well beyond the roof. Where water is near light fittings, switches or consumer units it is an electrical risk as much as a building one, and the supply to the affected area should be isolated.

Containing water and protecting the room is the first step; establishing the cause is the second. Doing the second without the first is how ceilings come down.

A roof line that has changed, timbers that have cracked or moved at a bearing, or a ceiling that is bulging or soft are all indications that loads are not being carried as intended. These are assessed promptly, and the affected space kept clear in the meantime.

Slipped slates and tiles resting on a gutter, loose ridge components, cracked chimney pots and detached leadwork are all falling hazards. Above a pavement, entrance, drive or garden in use, that risk is the reason to act rather than the state of the roof itself.

A leak that returns after two or three repairs is usually evidence that the cause was never identified, that water is entering somewhere other than where it appears, or that more than one defect is contributing. Repeating the same repair a fourth time is rarely the answer.

At that point the useful step is a proper diagnostic exercise: internal inspection, external survey, and if necessary water testing, before any further work is priced.