Typically these metal roofs are found on larger pre engineered metal buildings.
How to keep a metal roof from leaking.
Once you use urethane roof cement and apply the new patch you have to do it correctly.
Secondly in order to prevent leaks the self drilling screws that attach steel roof and wall panels must be drilled in straight not crooked.
If not tightened enough the washer does not form tight seal and may leak.
If the seal is overtightened the over compressed may leak.
Stack flashings another area very prone to leaks on a metal roof is the area around stack flashings.
These larger structures are more costly to design with a steep sloped roof assembly.
Hydrostatic metal roof systems are designed to hold water until it can drain.
Another thing to note is to use the proper urethane cement suitable for your roof.
Recaulk the corner flashing if any areas have hardened caulk.
These roof systems are capable of holding water without the roof system leaking.
Dig out any cracked or dry caulking that isn t properly sealing adjoining surfaces and replace with silicone caulk.
Thirdly screws with washers must be drilled to the correct depth.
Metal roofing screws roofing screws are responsible for the majority of leaks on metal roofs.
An extension of at least six inches is good enough to secure the holes and gaps effectively.