Insulation applications and building science.

Thoughts on a couple insulation applications? Haven’t seen any mildew or mold issues in either of these examples but with mold training from NACHI, I’m trying to get input for better knowledge. Mountain climate with warm summers but cold winters.

First scenario: Wood I-joists with 1/2 inch thick center cord 16 O.C. have a little wider span between them than normal 1 1/2 thick dimensional lumber. I have seen the use of slats lying across the 2X band on the lower edge of the joist to support the insulation but this allows an air space between the insulation and the subfloor. The other option is using tiger teeth to hold the insulation against the subfloor even if you have to cut them from 24 OC tiger teeth. Any input?

Second scenario: Same climate, Masonry block church building with programmable gas forced air heat. Interior furred and drywalled. No insulation. Dry, hilltop location with good drainage, 12 inch overhangs. 2 inch thick hard foamboard insulation on the outside of the walls with airspace between it and metal vertical siding. Heat varies in building several cycles per week as thermostat warms for services then drops back down. Much risk of mold?