here are two ways to find out.
The easy way is to use our space calculator, you can find it here.

The other is the manual way.

	Measure the height of your object.
	Measure the length.
	Measure the width.

Convert measurements to meters if they are not already. If measurement was taken in millimetres, divide by 1,000. If by centimeters, divide by 100.
Multiply the three measurements. The answer is given in cubic meters.

Do this with every item you want to store and add up the results.
Rule of thumb is to add an extra 5 cubic metres to it just to be on the safe side.

This is your magic number. Considering that all of our units are 3 meters high you need 6×3 meter unit to store 54 cubic meters (3×6x3).