JD4

Seasoned timber: Joint group 4. For timber joint design, JD1 (highest) to JD6 (lowest).

For timber joint design, timber is classified into six joint groups—JD1 (highest) to JD6 (lowest) for the seasoned or dry condition.

Joint groups for unseasoned timber (J1 to J6) are provided only where published, basic density data were available.  
For species groups, the joint classification uses the lowest density applied to a species in the group.

Used in field: