Why does my roof only leak in heavy rain?

It can be frustrating when your roof stays dry during a light drizzle but starts dripping during a Melbourne downpour. This usually points to a "capacity" or "pressure" issue rather than a simple hole.

Common reasons for heavy-rain leaks

• Valley gutters overflowing: During heavy rain, valleys carry a large volume of water. If they are partially blocked with debris, they can overflow into the roof space.
• Box gutters: Often found on Melbourne terraces, box gutters have a limited capacity. If the downpipes can't keep up, the water backs up and enters the building.
• Flashings: Wind-driven rain can be forced under flashings that would otherwise deflect vertical rain.
• Skylights: The seals around skylights are under much more pressure when water is pooling or rushing past during a storm.

Paul specialises in finding these tricky leaks that only appear when the weather is at its worst.