Why are the transport costs of insulated storage buildings higher than that of non-insulated storage buildings?

The transport volume of an insulated storage building is 3 to 4 times greater than that of a non-insulated storage building. The insulated sheeting is 4 cm thick, that of non-insulated sheeting is only 0.4 mm thick. The skylight panels of a non-insulated storage building are also much thicker than those of an non-insulated storage building. The insulated storage building has an insulated overhead door as standard. This door takes up much more volume than the standard roll-up door of an uninsulated storage building. Due to the larger volume, we cannot combine the transport of the warehouse with the transport of other products. This means that we must arrange transport for just one address. As a rule, this is always more expensive than a combined transport.