These signs will tell you that you may have a leak in your roof.  1.There's a Water Stain. A water stain may look like a large  puddle on the ceiling, often ringed with brown. 2.Sometimes There's a Drip. 3.There Are Spots on Your Exterior Walls. 4.Your Walls Are Growing. 5.You See Missing Shingles or See Debris In Your Downspouts. Remodeling Advice, Richmond Hill, Raiding