According to roofing regulation laws, it is legal to install a new roof on top of an existing roof, if there is only one layer of roofing already existing. If your building already has two layers of roofing, however, we will need to perform a tear-off before we can install your new roofing. Also, if the existing roof is deemed unsafe (damaged, saturated with water, or unstable), we need to tear off that layer of roofing as well.