Shop insulation question

I have a 12x20 on slab building that was studs and open ceiling to rafters when we moved in. I insulated the walls and put up 1x6 T&G all around and put a window unit in the rear facing window. This has done a good job of keeping it relatively comfortable to work in there. However, the ceiling is still open and you can see the radiant decking underside. I was putting some stuff over the ceiling today and the temp diff between the ground and attic area is huge. I’d like to keep the ceiling open for access to storage. Would placing R30 faced batt insulation between the rafters create any kind of potential moisture issue?