Bearing Plate Washer (BPW)

Z4 Bearing Plate Washers (BPW) are the interface between the Tie-Down System and the level of the building being anchored to the foundation. As the floor system is pulled upward by shear wall over-turning forces, pressure is applied to the BPW/CNX assembly and transferred into the Z-Rod/all thread rod (ATR). The required bearing area is based on the design uplift to minimize crushing of the wood and the plate thickness must be sufficient that bending does not limit the capacity of the system. The wood species is also a factor when sizing. The pounds per square inch (psi) of compression cannot exceed the allowable compression perpendicular to the grain of the wood species it is bearing on.