Damage can be caused by natural disasters such as extreme wind conditions, heavy rainfall, dust storms and other natural phenomenon. Since shingles are supposed to shed water, broken, torn or missing tabs become obvious entry points for water. These entry points leaking is more common on low slope roofs where run-off is slower and at peaks of the roof where shingles are the most vulnerable to high winds. Many problems occur at the flashings and around vents, soil stacks, chimneys and vertical wall joints.