Leviticus 14:38

36The priest shall command that they empty the house, before the priest goes in to examine the plague, that all that is in the house not be made unclean. Afterward the priest shall go in to inspect the house.

37He shall examine the plague; and behold, if the plague is in the walls of the house with hollow streaks, greenish or reddish, and it appears to be deeper than the wall,

38then the priest shall go out of the house to the door of the house, and shut up the house seven days.

39The priest shall come again on the seventh day, and look. If the plague has spread in the walls of the house,

40then the priest shall command that they take out the stones in which is the plague, and cast them into an unclean place outside of the city.