I have read the following paragraph from Diary of a Wimpy Kid 3:
Ever since Mom assigned the dishes to me and Rodrick, Dad's been going down to the furnace room after dinner to work on this miniature Civil War battlefield of his.
I am confused about the meaning of "furnace room". I have looked it up in the dictionary.In the dictionary, it means:"a large container for a very hot fire, used to produce power, heat, or liquid metal."
How can he build a furnace room at home. I think it means "basement",but I can't find this meaning in the dictionary.