Sprinklers for concealed space with metal trusses and wood sheathing covered by insullation

[JCianfarra]

Forum,
I have a case in an NFPA-13 building that has an attic space above a suspended ceiling. The pitched roof above it constructed of metal joist and metal trusses and covered by wood sheathing. Directly under the roof covering the wood sheathing is a layer of R30 incapsulated vinyl faced insulation. Does this essentially create a non-combustible or limited-combustible concealed space since the wood sheathing is not exposed and the structure is steel? Thanks, Joe C.

 

[cdafd]

Need to look at 13, but to me if you look up and can see wood,if the indulation was nit there, you have a combustible space , as in sprinklers required

 

[Sdpaddler50]

Based on how you describe this, and from a peformance based standpoint - I would say you have a combustible, concealed space. If a fire starts in the space, and the vinyl faced insulation burns away, the fire will then spread to the wood. At this point, it is probably good bye building. Non protected, concealed spaces have been the cause of some of our worst fires.