Poking holes in metal roofs invites leaks. And with pre-engineered standing- seam metal roofs, the contractor can easily get caught without the protection of a manufacturer's warranty. That's because these roofs are designed at a factory – and it's next to impossible to design for every problem that can occur in the field. Before signing up to install a manufacturer's roofing system, the contractor had better take a good close look at the details. Wherever pluming vents, skylights, scuppers, or parapet walls penetrate or join the roof, there's a chance leaks will occur. These roof penetrations can also cause the roof to self-destruct. If the manufacturer's manual shows these roof penetrations clearly, and if the details make sense, the contractor
