Preservative Treatment and Truss Plates

Special attention should be given to service conditions such as wet service and an associated
treated service condition. Truss plates should not be used in incised lumber. Agricultural
buildings can sometimes give rise to corrosive environments that require special measures such
as a higher standard of galvanization such as a G185 coating class or even use of stainless steel
truss plates instead of the typical G60 coating class used in the U.S. or G90 coating class used
in Canada. As of January 2003 new preservatives such as Copper Quat ACQ or Copper Azole
CBA-A or CA-B were introduced in the marketplace to treat wood. These may also require G185
coating class or stainless steel truss plates. Further guidance on the use of trusses in special
environments may be available from your regional truss association.