1 Kings 6:8-10

8The entrance to the side-chambers of the middle [floor] was in the right side of the house; and they went up by winding stairs into the middle [floor], and out of the middle into the third.

9And he built the house, and finished it; and covered the house with beams and boards of cedar.

10And he built the floors against all the house, five cubits high; and they held to the house by the timbers of cedar.