“How much is the height under the fermi? ” – this is a question that can be heard quite often from the mouths of installers. However, there is also space from the bottom of the fermi to the ceiling that could be used for storage. A normal warehouse roof sits on top of ferms with posts 6000 mm apart from centre to centre underneath. It would be wise to leave the fermi to run between the rows of the double shelf. If the shelves need to be mounted on the other side, higher shelves could be used to give the possibility to store between the warehouse ferms. Cross fermed rows of the bottom shelf are a bit of a gamble, but again a way to gain more space.