Hi,
Variable overhead is something which is not a direct expense to build a product. The amount is consumed indirectly.
I can give you some examples of Variable overheads:
1. power consumption of a machine (because it will vary based on the product and other parameters.)
2. Consumables (such as oil, grease) that will depend on the usage of the machineries.
I hope you ve got it.
erpconsultant