Ok, I know foil bubble wrap has gotten some (deserved) hate here. Radiant barriers have also not fared too well. However I am wondering if I have a use case.

Uninsulated barn with metal roof on purlins. No sheathing, no ceiling. Planning on eave to ridge vents (which, yes, the entire barn is open to this vent path)

I am wondering if a radiant bubble wrap under the metal (stapled to purlins) would help to both reduce condensation drip and keep the barn cooler from radiant gain. Or more specifically, if it will do these things to a degree to warrant the install. The goal is not to make the barn cooler than ambient, but to keep it from getting hotter (or at least noticeably hotter). It is a sunny site.

I am also considering roof with a high Solar Reflectance Index, but the product we’re looking at doesn’t appear to have that data, and I don’t like the lighter colors as much aesthetically.