Leviticus 14:37-42

37He is to examine the house, and if the mildew on the walls consists of green or red depressions that appear to be beneath the surface of the wall, 38the priest shall go outside the doorway of the house and close it up for seven days.

39On the seventh day the priest is to return and inspect the house. If the mildew has spread on the walls, 40he must order that the contaminated stones be pulled out and thrown into an unclean place outside the city. 41And he shall have the inside of the house scraped completely and the plaster that is scraped off dumped into an unclean place outside the city.

42So different stones must be obtained to replace the contaminated ones, as well as additional mortar to replaster the house.