You might contact Henry's about their elastomeric roof coatings. On the link under #275, (click on the #275), water based white elastomeric roof coatings it states they have a variety of custom colors. The advantage to an elastomeric coating is that it remains flexible with temperature changes. Put some on my shop roof and it still looks great after 15 years. Longevity on most materials depends on geographic location despite manufacturers claims, but Henry's is a reputable coatings outfit.

Here is a link that might be useful: Henry's

Thanks, sierraeast. I'll check that out. I've been reading about the elastomeric coatings, and that might do the trick.

I've contacted Henry's and they do not support the use of their coatings on asphalt shingle roofs. I can't say why because htey didn't, just that their product s not for use on asphalt shingle coatings. One company that does put it into print that asphalt shigles are an acceptable substrate is BlackJack's Sta Kool 770. Though I can't find it in stores...