Heat Treated Lumber
What does KD-HT mean?
Western lumber mills and others are producing lumber showing a KD-HT mark, indicating the wood has been kiln dried and heat-treated.
The KD-HT mark was added to meet new European Union regulations for wood pallet and crating materials. The mark indicates that the lumber has been heated to a core temperature of 56°C for a minimum of 30 minutes and is dried to a maximum moisture content of 19% or less.
Many mills are adding the new designation to grade marks. For structural framing applications, including wood trusses, the KD-HT mark can be considered the same as DRY and KD.
The HT mark does not affect the structural capacity of framing lumber regardless of the grade and its end use.