Returns the value of LiningThickness attribute. This attribute represents thickness of the window lining as explained in the figure above. If LiningThickness value is 0. (zero) it denotes a window without a lining (all other lining parameters will be set to "unset" in this case). If the LiningThickness is unset it denotes that the value is not available.
Returns
Returns the value of LiningThickness attribute.
Remarks
IFC4 CHANGE: Data type modified to be IfcNonNegativeLengthMeasure.