article from Business Insider.
The article talks about using a fiberboard roof coating and then using a coat to keep it from sticking together, which you can do by covering the entire roof with it.
Business Insider has a lot more of this type of article on the web, so if you want to check it out, check out this one.
If you are a roofing expert, you may want to read this article from Architectural Digest about how to create the best roof coatings.