What roof valleys do
Valleys are the metal channels where two sloping sections of roof meet. They carry a large volume of water off the roof and into the gutters — during a downpour, far more water flows through a valley than over any single tile.
How they get blocked
Mackay's lush vegetation and coastal winds mean leaf litter, twigs and debris steadily build up in these channels. Left alone, that build-up acts like a dam across the valley.
When an intense downpour hits, the water can't escape down the channel fast enough. The level rises, then flows sideways over the edges of the valley, bypassing the flashing and running straight into the roof cavity.
Quick tip — A roof that handles light rain fine but leaks in heavy storms can point to valley overflow — the channels simply can't keep up once they're partly blocked.
Keeping valleys clear
- Debris visible sitting in the valley channels or against the flashing
- Overflowing gutters near valley outlets during rain
- Plants taking root in built-up litter on the roof
- Leaks that only appear during the heaviest downpours
Why it's a maintenance win
Clearing valleys is one of the cheapest, highest-value pieces of roof maintenance there is. Keeping the channels and gutters free of debris lets the roof drain the way it was designed to — and prevents a blockage from turning into water damage inside the home.
Think this might be your roof? Get a free, no-obligation quote from a local Mackay tiled-roof repairer. Get in touch →