Underground room arrangement

An underground room arrangement, comprising:

• a structure surrounding a room, the structure comprising a plastic tube and plastic end walls, wherein the plastic end walls are arranged to close the plastic tube so that inner surfaces of the plastic tube and the plastic end walls are towards the room;
• wherein a wall of the plastic tube comprises a hollow;
• wherein the hollow is a spiral hollow spiraling in the wall in an axial direction of the plastic tube;
• wherein the wall of the plastic tube is construed from at least one spiraling hollow plastic pipe;
• and
• wherein the at least one spiraling hollow plastic pipe has a rectangular cross section, wherein
• a first side of the rectangular cross section of the at least one spiraling hollow plastic pipe towards the room forms an inner surface of the plastic tube;
• a second side, opposite the first side, of the rectangular cross section of the at least one spiraling hollow plastic pipe away from the room forms an outer surface of the plastic tube;
• and
• the at least one spiraling hollow plastic pipe spirals in the wall in the axial direction of the plastic tube spiraling between the first and second sides of the rectangular cross section.