Air barrier strategy / Discussions

...air gap behind the Board and Batten).  Barn will be heated by radiant floor heat. Will this type of insulation work?  Do I need to place a vapour or air barrior on top of the 3/4" Shiplap Pine prior to emplacing the Rigid Panels?  Do I need to place a Tyvek type sheathing over the insulation between it and the Board an...

...airspace to speak of). The interior plaster and lathe is cracked and damaged.  The plan is to remove the existing trim and plaster/lathe to have full access from the interior to the wall cavity.  Then insulate with Rockwool batts + Rockwool rigid board over the studs to provide a thermal barrier + Intello (or other) ai...