Commercial roofing systems that have safety rails will have several possible on-going issues.  

  1. The rails need to be monitored for rust and rot.  This can require major overhaul and replace of the railing systems if maintenance is not developed.
  2. Penetrations need to be correctly installed, and anchored to the substructure.  Usually pitch pockets will be poured around the rails that are there. Note: If the railing system is loose, call a General Contractor or Roofing C  ontractor immediately.
  3. Codes-specifically the IRC say that the railing systems have to be 42” tall for safety.  Usually your older iron railing systems may not be this height.
  4. A few years ago, this owner put a rolled roof membrane over this low slope.  The roof is having issues, ponding water, and leaking. So asphalt type rolled roof does not like ponding water, and they have a greater chance of leaking.
  5. So in summary, single ply, like TPO roof works best here.  Make sure and check your railing and penetrations for Codes and functionality.