An enclosure includes a furnace 1 and plates 7A to 7D arranged in the furnace 1 and used for placement of articles 5. Each of the plates 7A to 7D is movable vertically in the furnace 1. The enclosure further includes guide members 60A and 60B, each of which is disposed adjacent to a side of one plate of the plates 7A to 7D that is disposed at a loading/unloading position where the articles 5 are allowed to be loaded into or unloaded from the furnace 1. The guide members 60A and 60B guide the articles 5 and are rotatable with vertical movement of the plate.