Firstly you must find out if the goods measurements exceeds the weight. Voluminous cargo is either cubic meters/m3 or loading meters/LDM. Loading meter goods (LDM) equals goods that cannot be combined and is non stackable. E.g. goods can be damaged if we load other goods on top, cannot double stack the pallets or dangerous goods. 1 EUR pallet = 0.4 LM.
Cubic meter (m3) is calculated when the goods can be placed on top of other shipments when the weight is low. Calculating CBM can be done by measuring: length x width x height. 1 m3 = 333 kg.
It will not cost less in shipping to send more by weight. The prices are given weight groups, which means that they decrease for each weight group. For consignments that are close to the next weight bracket, it can look cheaper to send, for example, 1100 kg than 960 kg. The general rule for these is that the maximum amount in one weight group will be the minimum amount in the next group.