Parashas Metzora · Passuk 14:39
Chabad.org — English translation + Rashi
Torah Temima points to Toras Kohanim.
English: “In the walls of the house” — and not in the walls of the side-chamber, nor in the walls of the manger, nor in the walls of the partition, nor in the walls of the lamp-stand.
Limitation to main walls
Chazal restrict the second inspection to the primary walls of the house; secondary structures are excluded from this particular examination.