If you want to find a leak on your Toronto roofing, you need to pour water on the shingles. Water will always stream straight down with gravity. Blockages, skylights, and cracks are the most typical leakage sources. Start by taking a look at the chimneys, plumbing vents, and skylights. Then inspect roof-to-wall transitions where flashing takes place, such as dormers, eaves, and valleys.