If bees build a hive on your roof, it can cause several problems. First, the weight of the hive can damage the roof structure. Second, the bees can enter your home through cracks and crevices, which can be a nuisance and even a health hazard. Third, the bees can produce honeydew, a sticky substance that can attract other pests, such as ants and wasps.
If you find a beehive on your roof, it is important to remove it as soon as possible. You can do this yourself, or you can hire a professional pest control company.