the 2017 edition is useful, but treat it as a reference – not a construction specification – unless the design is still actively listed by UL today. Final Pro Tip: If you find a 2017 design number online, look it up in the current UL Product iQ . If it is still active, UL will show it. If not, the design has been withdrawn or modified. Never build from an obsolete design.
If you are working with an older building code, verifying a legacy design, or performing forensic analysis on a structure built before 2018, you may need the 2017 UL Fire Resistance Directory . ul fire resistance directory 2017 pdf
Published annually by Underwriters Laboratories (UL), this directory (often called the "Orange Book" or "Yellow Book" for its historic cover colors) is the definitive guide to fire-resistive assemblies . It contains thousands of tested and certified wall, floor, column, beam, and roof designs (designated as "U300," "U400," "D900," etc.). the 2017 edition is useful, but treat it
