A homeowner from North Carolina wrote and asked me:
I have a question –If I go with the dark green color what does it do to reflecting the sun –will it absorb and heat the house? Thanks
Dark colors, regardless of the type of roofing, are more absorptive of heat, than are light colors. Absorbed heat ends up in your attic and must be vented out. It can also affect your air conditioning loads.
Now, with metal roofing, many companies now offer paint finishes with reflective pigment so that, even in dark colors, you will reflect radiant heat and reduce the attic heat gain.
If you are concerned about attic heat then I would suggest finding a metal roof which has reflective pigment in its coating.