תלמוד על בבא בתרא 2:4

MISHNAH: A person should not put an oven in the house²³The ground floor which either has a dirt or a stone floor. Therefore, no fireproofing is needed below the oven. But the ceiling, which also is the floor of the second storey, is made of logs covered with plaster; it is flammable. unless there be above it a space of four cubits; or if he puts it on the upper floor unless there be under it insulating material three handbreadths and for a stove one handbreadth²²If the stove is used inside the house, it needs fireproofing material on the floor, the ceiling, and the nearby wall. But if he caused damage, he must pay what he damaged²⁴Even if he observed all rules spelled out in the Mishnah.. Rebbi Simeon said, the reason they indicated these measures is that he not be liable to pay if he caused any damage,.