Ridge capping cracked and broken
This is the main cause of a leaking roof. A roof will always move gradually over time and due to this the cement that holds the ridge caps to the tiles cracks and gives way, leaving holes for water to seep through.
Broken Tiles
This is another very common cause of a leaking roof. Even though there are many different designs of tiles there are actually two main types of tiles, Cement and Terracotta. Terracotta tiles are baked in a kiln and are very durable. Cement tiles are made from cement and not quite as durable but over time both these types of tile can crack.
Why are there broken tiles on my roof?
Often times you will discover broken tiles on your roof after you have had some sort of maintenance or installation work done on your roof e.g. Solar heating, Arial instillation or removal, skylight instillation. This is from tradesman walking on your roof without proper knowledge of how or where to walk on tiles and will more often than not crack a tile or two.
The older the roof the more fragile the tiles are and easier to break.
Clogged up gutters
The walls of most gutters are often shorter on the side that are flush with the eaves of the roof. So when gutters are clogged up, water will fill up in the gutters and spill over the shorter side and can leak into your eaves and then pool up or trickle to the rest of the roof.
Clogged up roof valleys are another issue. Leaves can work themselves underneath the tiles that overlap the valley iron. This isn’t an issue in itself but when it rains, these leaves make it easy for water to follow get under the tiles and then leak into the roof.
Often a simple cleaning of the gutters and valleys can help many leaks in your roof.
Also in addition it is very important to keep your gutters clean during the summer time with bush fires and house fires very common, since leaves are an excellent fuel for fire, sitting all around your house.