Dark color is more likely to contribute to overheating in the summer. It can help with heavy mass walls, but won't do much good for an insulated wall. Heat that is produced, will be quickly lost to the cold wind. Dark paint and especially dark shingles, can have a short lifespan, due to overheating.
he who throws mud loses ground -- this tiny ad is sitting on a lot of mud:
Experience months or even years of natural building and growing your own food