Every time you define a new nested `section` or `article` within a document it is recommended to start your headings with `h1` tags. It is only within that same `section` or `article` that you need to descend the headings. 

The reason for this is:
> The article element represents a component of a page that consists of a self-contained composition in a document, page, application, or site and that is intended to be independently distributable or reusable, e.g. in syndication. 

http://html5doctor.com/the-article-element/