[philb]

"If you paint the roof, get some of the microscopic glass beads to spread on the wet paint of the roof. They tend to help reflect heat load (and in the moonlight, your roof can appear to 'glow' with reflecting the moon light)."

Servant74, the beads never occurred to me. That's a great idea. They are also available as 'micro spheres' through several aircraft supply houses for lightning up fiberglass resin. The cost is reasonable.

A second inside roof to provide shade and a breeze through the void is the easiest way. Be sure not to forget to vent the peak of the roof.