CIL chargeable floorspace - retail storage - Public forum - Planning Advisory Service (PAS)

Hi - We have received a planning application for the retention of 2 storage containers located in a service area to the rear of an existing retail premises. I cannot find anything in the guidance which points to whether or not ancillary storage would fall within the definition of retail floorspace and would therefore be CIL chargeable.  Any advice on this would be very welcome.  Thanks