Negaim, Chapter Thirteen, Mishnah Three
1) A house in which a nega appearedif it had an upper chamber above it, the beams are considered part of the upper chamber.
2) If the nega appeared in the upper chamber the beams are considered part of the lower room.
3) If there was no upper chamber above it, its stones and wood and earth must be torn down with it.
a) He may save the frames and the window lattices.
b) Rabbi Judah says: a frame that is built over the house must be torn down with it.
4) Its stones and wood and earth convey uncleanness if they are of the minimum size of an olive.
a) Rabbi Eliezer Hisma says: whatever their size.
Section one: The beams referred to hold up the ceiling of the bottom floor, which is the floor of the upper story. If the nega appears in the lower story, he need not tear down these beams. Rather, he can leave them and prop them up temporarily in order to use them to rebuild the house.
Section two: If the nega appeared in the upper chamber, he can consider the beams as part of the bottom story and leave them there. We see that the rule is lenient in both cases.
Section three: This is the standard rule with regard to tearing down the house. He must tear down all of the stone, woods and earth parts of the house, even if they were not afflicted with a nega. In this case, because there is no upper chamber, the beams used as part of the ceiling can only be considered part of the house, therefore they too must be torn down. He may save the frames of the doors and the windows and the window lattices. Assumedly, he can use these in rebuilding the house.
Rabbi Judah says that if there is a square frame that is built over the house, it is considered part of the house and it too must be torn down.
Section four: The stone, wood and earth that have been removed from the house are ritually unclean. They convey uncleanness if there is a minimum amount the size of an olive, the typical amount required to convey ritual uncleanness. Rabbi Eliezer Hisma rules more stringently. It doesn’t matter how little there isit ritually defiles even if there is the smallest amount.