Steel roofing systems have become popular due to their high durability and fire resistance. There are two basic types of steel roof systems: concealed fastener and exposed fastener systems.
Concealed fastener steel roofing is the more expensive option. The steel roofing shingles are shaped so that the fastening bolts and nuts are hidden within the interlocking folds of the steel roofing. The advantages of this type of steel roof system are that it is more aesthetically pleasing to look at as well as not requiring the extra sealant and upkeep that exposed fastener steel roofing requires.
An exposed fastener steel roof system is less expensive than concealed fastener steel roofing, but tends to be less aesthetically pleasing. This type of steel roof system requires that the panels be secured into the roof decking. Then, extra sealant application and maintenance around the exposed bolt and nut holes must be performed to prevent water leakage.
Even though steel roofing is more expensive initially than conventional roofing materials, it will last longer and require less overall maintenance. Cost and aesthetics, as well as upkeep are things to consider when choosing between a concealed fastener and exposed fastener steel roof system.