Common Causes Of A Leaky Roof
You might be restoring your roof to get it back to its pristine best. But before that, you need to make sure everything seals securely. Leaks can cause mould and rotting and can lead to unnecessary expense down the track. Here are some of the most common causes.
A fertile ground for roof leaks is around anything that projects from the roof, such as chimneys, roof vents or plumbing elements. Flashing, often made of sheet metal, is the material that runs around the rims and edges of these objects, to securely attach them to the roofing. This flashing can weaken over time due to exposure, letting water seep through. In these cases, you need to replace the flashing. However, the problem might lie instead with the tightness of the seal between the flashing and the roof. The bonding mortar that holds everything together could have broken or fallen away. In these circumstances, the flashing needs secure re-attachment.
Even though leaks develop less commonly in open areas of tiles, drips in these clear sections are possible. Chipped, cracked or displaced tiles can allow water to trickle through. You will then need to replace any damaged tiles with ones of the same size and profile or shape. If that's not possible, you might be able to repair them with an epoxy resin filler. Storms and gales can dislodge tiles, and you won't necessarily be aware of this until the water damage inside becomes evident. You need in these situations to reposition the tiles securely.
Ravaged Ridge Caps
The ridge on a roof is the peak where the two roof planes meet, forming a straight mountain-like peak. Similar to any roof join, it carries the potential for rainwater to leak through. To deal with this, a ridge cap runs along the join, covering it; this cap might consist of cement mortar or metal (on a metal roof). Problems can occur with this if the cement mortar cracks and falls away to expose the vulnerable join. It just then needs to be redone. Alternatively, a metal ridge cap might weather or become dislodged.
Wrong Roof Pitch
Another possible cause of roof leakage relates to the roof pitch angle. Each manufacturer designs and produces tiles of specific sizes and profiles for roof pitches of a particular angle or steepness. If the roof is flatter than recommended, it can then leak because the water is not draining off as it should.
In these cases, the roof might need sarking. That is, you need to lift the tiles and tile battens and to place sarking materials, such as reflective foil insulation, underneath to prevent water pooling on the roof and leaking inside. Roof restoration services can advise further about recommended roof pitches and tile profiles.