How to Identity Roof Leaks

The condition of the roof covering. This includes cracked, broken or dislodged tiles or slates, damaged or corroded roof sheeting, weathered thatch. Incorrect installation can render any type of roof coverings ineffective.

Leaking roofs are a common issue identified in home inspections. Home inspections show that there is main issues to think about when diagnosing & fixing leaking roofs:

Weak points as regards potential leaks are the areas where roof surfaces intersect with walls, chimneys or other roofs. These intersections are usually weather-proofed with "flashing" of kind or another.
Tiles The home inspector will check for cracked, broken or dislodged tiles or slates. Poor installation techniques which may finish up in leaks include: Cracked mortar on ridge or barge capping tiles; lack of mechanical fixing of tiles in vulnerable areas along eaves & ridges & a roof pitch which is low.
Roof sheeting Metal roof sheeting often corrodes along the overlaps & around the fixing screws. Too-short end-laps & inadequate side-laps which face the prevailing weather are common installation mistakes. Cracked & weathered fibre-cement or plastic roof sheeting may even be an issue.
Thatch The top layer of grass in a thatched roof, which is exposed to the elements, slowly rots & needs to be periodically combed out & replaced to preserve the weatherproof qualities of a thatched roof.
Roof pitch The South African National Building Regulations prescribe maximum pitch levels for roofs - depending on the roof covering.
Finding the leak Roof leaks are mostly noticed from inside the house - damp patches on the ceiling or on walls. Because water often tends to run down the roof timbers before manifesting itself in a visible damp spot, detective work inside the roof cavity is often useful in determining exactly where the roof is leaking. Damp staining on the top chords of the roof trusses & sometimes spots of daylight visible through the roof covering are often the best indication as to where the leak originates.

The pitch of the roof. Usually only "flat" roofs are water-proofed; most pitched roofs are "weather-proofed". This means that the roof is designed to shed water quickly to prevent rain water from penetrating the roof covering. Usually speaking, the steeper the pitch of the roof, the less likely it is that the roof will leak.