Freeze-thaw damage in roofing primarily occurs due to moisture that is trapped within roofing materials. When the temperature drops, this moisture can freeze, expanding and exerting pressure on the materials. As the temperature rises, the ice melts, causing the materials to contract. This repetitive cycle of freezing and thawing creates stress on the roofing materials, leading to cracks, deterioration, and eventual failure.
The presence of trapped moisture is particularly critical because it can originate from various sources, such as rain, snow, or humidity that infiltrates the roofing system. When the roofing materials are not designed to properly manage this moisture, the risk of freeze-thaw cycles causing damage becomes significantly higher.
Insufficient insulation, ice build-up in gutters, and a poor roof pitch can contribute to conditions that may lead to freeze-thaw damage, but they do not directly cause the damage to occur. The key factor in freeze-thaw damage is the trapped moisture itself and the physical effects of the freeze-thaw cycle on the roofing materials.