https://www.iko.com/blog/guide-flat-roof-systems/
Underneath the basics, flat roofs are usually constructed with a ceiling, nailed to joists which support a deck (usually wood in residential construction), a ...

https://www.billraganroofing.com/blog/best-material-for-flat-roof
The 4 Best Materials for a Flat Roof - 1. EPDM membrane roofing. EPDM (ethylene propylene diene terpolymer) is a synthetic rubber black membrane ...

https://www.americanweatherstar.com/flat-roof-materials-which-perform-best/
Common Flat Roof Materials - Modified Bitumen - Built-Up Roofs (BUR) - EPDM Rubber - Single-Ply (PVC, TPO) - Spray Polyurethane Foam.