1. General: "Roof Drainage - Not My Problem...Maybe" by John Lawson is a very readable although sometimes highly technical article on the necessity of adequate roof drainage and the potential consequences of inadequate drainage. It's available at the Digital Commons section of the California Polytechnic State University website.
3. Codes: The "Roof Drainage" section of the 2015 International Residential Code.
5. Drains: See here.
6. Gutters: See here.
7. Inspection of roof drainage systems: Mastering Roof Inspections: Roof Drainage Systems, Part 1 at the International Association of Certified Home Inspectors' website is worth taking a look at. Part two of this inspection guide can be accessed from this page.
8. Scuppers: See here.
9. Technical: Siphonic Drains: "The Fundamentals of Siphonic Roof Drainage System Design" is an easy-to-read introduction to this space-and-material-saving drainage innovation. Available to read on the website of Ron Blank & Associates, Inc.