First of all, we need to remove the black roofs from the roof. After that, we need to carefully and carefully mark the points for drilling. It will be necessary to drill holes in the roof in the gutter where the filler was. It is recommended to use high-strength drills for work as the roof has several layers of metal. The perverted holes must be processed by the anticorrosive coating and sealant. You can then install the railing.
If the holes were correct, the railing would be set without problems.