What can I store in my garage? Storing items in garages and outbuildings - substance permission There are items you would not be allowed to store in your garage - including explosives, oxygen, acetylene or other flammable gas bottles, or the storage of large quantities of dangerous substances. Contact OneCALL 0345 8 507 507 if you are unsure about an item, for further information or to obtain any necessary permissions. Keywords storage ; garage ; safety