WHAT DOES RUBBER INSULATION MEAN?

Would these skinny partitions also have to have a baffle to allow all-natural ventilation on their own outdoors walls, or is the fact that overkill?Conversely just the R15 in a 2x4 wall previously satisfies or exceeds IRC code min for zone 3, even though derating the rock batts for not owning an exterior side air barrier.Roxul manufactures several