The valley is the channel where two roof slopes meet, and it carries more water than anywhere else on the roof. This concrete tile roof in Abbotsford had a valley that was leaking by the time we got there.
Why tile roof valleys leak
Once we removed the tiles along the valley, we found the metal valley flashing packed with moss and debris.
Here is what happens. When debris builds up in the valley, it acts like a dam. Water runs down the roof, hits the buildup, backs up, and jumps over the valley flashing onto the underlay. The underlay is not made to carry water like that, so it works its way through and shows up as a leak inside.
How we fixed it
We pulled the tiles along the valley, cleaned the valley flashing out completely, and sealed it where it needed it, then reinstalled the tiles. With the valley clear, the water runs straight down and off the roof the way it is supposed to.
Keep your valleys clear
Valleys collect everything that washes down the roof, so they are one of the first places to clog, especially with trees nearby or moss on the tiles. Keeping them clear is simple maintenance that prevents this kind of leak, and it is a lot cheaper than fixing water damage inside.
If you have a stain on a ceiling below a roof valley, or you can see debris building up in your valleys, get it looked at. We repair concrete tile roofs across Greater Vancouver and serve Abbotsford and the Fraser Valley. Call 778-389-5564 for a free estimate.