Hello, I need advice about valley flashing. I have a roof and dormer with S tiles. The dormer is located at about the middle of one side of a gable roof. The dormer is triangular with its rakes ending at the gable roof, as shown in the simplified picture.
Start with a shorter piece of valley 2-3 feet. Angle it up slightly and cut off flush against the tile it should be dumping water out on. Insert malleable material; flex flash, lead, figaroll etc. as an ‘apron’ to extend the valley onto the necessary tile. The apron should be wider than the valley metal so you can fold back the edges to create a hem. The trick is to not try to force the water to run uphill to get out. These areas are a pain and one of the many things I hate about S-tile.
Thanks Tileman for your suggestion. I tried an aluminum “apron” and it’s tough to get that “angle up” to be flat because of the shape of the S tile. I am ordering a 2x2 lead sheet to see it it is better but I can’t see how I can avoid going uphill at that particular transition spot.
You will go a little uphill, it’s unavoidable, just have to minimize as much as possible. It’s a balance. If your apron goes under your valley metal a good 12 inches and has aggressive hemmed edges it will work. It does need to be maintained yearly if there are trees around.
Thanks again Tileman.