Roof problems worsen quickly if not addressed promptly. A small leak can turn into extensive structural damage within a month. This guide helps you identify the most common roof problems, understand their causes, and take the right action.
Roof leaks
A small leak can turn into extensive structural damage within a month. The sooner the problem is addressed, the smaller the damage and repair costs remain.A small leak can turn into extensive structural damage within a month. The sooner the problem is addressed, the smaller the damage and repair costs remain.A small leak can turn into extensive structural damage within a month. The sooner the problem is addressed, the smaller the damage and repair costs remain.
Moss and lichen
Moss and lichen grow especially on shaded and damp roof surfaces. They hold moisture against the roof surface, accelerating deterioration of the roofing material. Moss also clogs gutters and downspouts. Moss should be removed mechanically or chemically — pressure washing is not recommended, as it can damage the roofing material.
Ice dams and snow problems
Flashings (chimney, ventilation pipes, antennas) are the weakest points of the roof. Their seals deteriorate due to weather exposure and begin to leak. Regular inspection of flashings and replacement of seals is essential. The condition of chimney flashing should be checked with particular care.Flashings (chimney, ventilation pipes, antennas) are the weakest points of the roof. Their seals deteriorate due to weather exposure and begin to leak. Regular inspection of flashings and replacement of seals is essential. The condition of chimney flashing should be checked with particular care.Flashings (chimney, ventilation pipes, antennas) are the weakest points of the roof. Their seals deteriorate due to weather exposure and begin to leak. Regular inspection of flashings and replacement of seals is essential. The condition of chimney flashing should be checked with particular care.
Flashing damage
Ice dams form when heat escapes through the roof and melts snow on the roof surface. The meltwater flows to the eaves, where it freezes and forms a dam. The dam prevents water from draining and forces it to penetrate under the roofing material. The solution is to improve the roof's insulation and ventilation.
Roofing material wear and deterioration
All roofing materials wear over time. Sheet metal roofing coating wears and corrosion begins, tile surfaces deteriorate in frost, felt roofing hardens and cracks. Wear is normal, but maintenance significantly affects the rate. Regular condition assessment reveals wear in good time.
Repair or replacement?
A roof problem does not always mean the entire roof needs replacing. Localised repair is sufficient when the damage is confined and the roof is under 2/3 of its lifespan. Widespread problems or recurring leaks indicate a need for replacement. Request a free condition assessment — our expert will provide an accurate assessment and you can try the repair-or-replace tool.
Not sure whether a repair will do or the roof needs replacing? Try the Repair vs replacement calculator.
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Content reviewed and verified
Updated: April 2026
