Roof leaks during heavy rain can be a common issue and can occur for various reasons. Here are some potential causes:

Damaged Roofing Materials: Over time, roofing materials can degrade due to exposure to weather elements such as sunlight, wind, and rain. Cracked or missing shingles, deteriorated flashing, or damaged sealant around vents and chimneys can allow water to penetrate the roof.

Poor Installation: If the roof was not installed correctly initially, there could be weak spots or improper sealing that leads to leaks, especially during heavy rain.

Clogged Gutters and Downspouts: Debris such as leaves, twigs, or dirt can accumulate in gutters and downspouts, causing water to overflow and seep under the roofing materials instead of being directed away from the house.

Roof Pitch and Design: Low-pitched roofs or areas where two roof planes intersect (valleys) can be more susceptible to leaks, especially if not adequately sealed.

Condensation: Inadequate attic ventilation can lead to condensation buildup, especially during heavy rain, which may mimic a roof leak.

Ice Dams: In colder climates, ice dams can form at the edge of the roof, preventing melting snow from properly draining off the roof. This can lead to water backing up under the shingles and causing leaks.

Tree Limbs and Debris: Overhanging tree limbs can scrape against the roof during heavy winds or storms, causing damage that may lead to leaks.

Age of Roof: Older roofs are more prone to leaks as materials deteriorate over time and lose their effectiveness in repelling water.

To address roof leaks during heavy rain, it's essential to identify the source of the problem. This might involve inspecting the roof for visible damage, checking attic spaces for signs of water intrusion, and ensuring proper drainage systems are in place. Depending on the severity of the issue, repairs may range from simple fixes like replacing missing shingles to more extensive repairs such as resealing flashing or repairing structural damage. In some cases, it might be necessary to consult with a professional roofing contractor to assess and address the problem effectively. Regular roof maintenance and inspections can help prevent leaks and prolong the lifespan of your roof.

Ref: YolaSite