Design Manuals Design Manuals > CFDDM – Steel Deck on Cold-Formed Steel Framing Design Manual Design Manual – December 2017 Add to Cart DDM4 – Diaphragm Design Manual Design Manual – September 2015 Add to Cart FDDM2 – Floor Deck Design Manual Design Manual – June 2020 Add to Cart RDDM2 – Roof Deck Design Manual Design Manual – June 2020 Add to Cart