We have a flat roof (10 years old) and in Spring when the weather warms up, we tend to get leaks in the upper floor. During summer when it rains heavily, we do not get any leaks. What could be the cause of this? We have sealed all the areas on the roof that we thought might cause the leaks.
Answer:
Winter's frost is opening up a seam somehwere and that is what you'll have to track down. This may be a job for a pro.
