Net volume and Gross volume are pertinent for LCL shipments. Net volume is the estimated volume of your personal effects before palletizing or loading into liftvans (wooden crates). Gross volume is the post palletization or post crating volume of your shipment. LCL shipments are always charged based on gross volume.
You should expect palletizing to add 10-15% and liftvans to add 15-20% to your net volume.