Fortnite: Battle Royale Chest Map page contains a loot map
Head to the very back of the factory, as south as possible. There’s a chest inside the blue shipping container. Over the road from the container, there’s a parked garbage truck. Jump in the back for a chest. Head up toward the main factory building and this chest is at the bottom of a ramp, under an arch and behind a wooden crate. Up the ramp from the last chest and inside the room to your left. This chest is up the stairs, behind the conveyor belt.
Read full content : Challenges Map - Fortnite Battle Royale Map: Chest Spawn Locations
Outside the room with the previous chest, this one is to the north, in the shipping container by the car park. Walk out of the previous container and take a left. There’s a chest in the back of the parked car. East from the car park, there’s a chest at the top of Flush Factory’s main attraction: the towering toilet. Walk into the main reception. There’s a chest in the roof, on the other side of the wall from the enormous lorry outside. There’s a model bathroom inside the main factory building. Right beneath the mechanical claw is another chest. Be careful, as this loot often falls through the floor.