When a roof leaks, it can have many causes. Roof leaks can range from minor to severe, and the cost to fix them can vary as well. The first step is to understand what is causing the leak. Then you can hire a roofing contractor to fix it before it gets worse. You should have a roof leak dealt with as soon as possible to prevent further damage.
One common cause of roof leaks is cracked flashing. Flashing are thin pieces of metal that run under shingles and on the joints of the roof to form a water-resistant barrier. If they are exposed, they will look like long runs of sheet metal. If they are concealed, the flashing will have a rubberized coating on top. Flashing can break if the tar that is used to seal it corrodes over time. If the flashing is exposed, it could crack because of wind and rain.
Missing shingles are easy to spot. You will see patches of different colors on your roof. Shingles can be torn off by strong winds and heavy rain.
Valleys are areas where two planes of the roof come together. If valleys are not sealed properly, rain can get inside as it runs down the roof. This can happen if the valleys were not sealed properly, if they were stepped on and cracked, or if rain and ice caused corrosion over time. If the valleys are not sealed properly, you will see wet spots running along the seams of the roof.
Roof vents stick out of the top of a roof and expel moisture from the house. They are often sealed by putting flashing around the opening and slipping a rubber boot over the area where the pipes stick out of the roof. The flashing can break or the roof can decay over time, leaving dark spots and mustiness.
An ice dam is a ridge of ice that forms when heat from the attic melts snow on the roof and the water runs down the roof and refreezes. It forms a ridge of ice at the edge of the roof that prevents melting snow from draining and can damage the roof.
Leaks around the sides of skylights indicate that they were not installed properly. If you see leaks and wet spots near the top of a skylight, it could indicate a problem with the flashing. These problems can be caused by incorrectly measuring and fitting the skylight at the time of installation or decayed insulation along the edges of the skylight.
Gutters are designed to carry water away from the roof, but they can become clogged with leaves, sticks, and other debris. This can allow rainwater to pool in one part of the roof and seep through cracks.
Wear and tear can occur along the mud cap, the area with mortar around the top of the chimney. Holes can form in the mortared joints where the chimney is connected to the roof, and flashing and shingles can come loose in the surrounding area. These problems can be caused by mortar eroding due to harsh weather.
If there is mold or mildew in your attic or a strong, musty odor, this is a sign that there is a leak. Condensation and moisture can form because of temperature changes.
Walking on a roof too much can also cause damage. Many roofing materials are fragile, and stepping on them can cause or worsen cracks and other damage.