American Wood Council’s Flame Spread Guide Updated

LEESBURG, VA. – The American Wood Council (AWC) has released an updated version of Design for Code Acceptance (DCA) 1 – Flame Spread Performance of Wood Products Used for Interior Finish.

Primary changes in the DCA 1 include:

• Updates to reflect 2018 International Building Code (IBC) provisions
• Added reference to new ASTM E2579 and E2404 mounting standards
• Addition of Black Spruce 3-ply cross-laminated timber

Wood materials are permitted to be used as interior finish in most building occupancies. The 2018 IBC requires interior wall and ceiling finish materials to be classified based on flame spread and smoke-developed indices determined from testing under the ASTM E84 or UL723 test methods. The classifications then set conditions of use for interior finish materials in various occupancies and building locations.

“The flame spread index for a specific wood product is usually obtained from the manufacturer, but code officials and designers can make use of DCA 1 to determine the flame spread index for many lumber species and various engineered wood products,” said AWC Manager of Engineering Technology Jason Smart, P.E.

DCA 1 provides flame spread indices for various wood species across a number of wood products normally used as interior finishes for walls and ceilings. All of the wood species and wood panel products listed in DCA 1 qualify as either Class B or Class C, and all have smoke-developed indices less than the limit required by the IBC.

Updated DCA 1 can be found on the AWC website: awc.org/codes-standards/publications/dca1.