1 Kings 6:13

He built the floors all along the house, each five cubits high; and they rested on the house with timbers of cedar.

The LORD’s word came to Solomon, saying,

“Concerning this house which you are building, if you will walk in my statutes, and execute my ordinances, and keep all my commandments to walk in them, then I will establish my word with you, which I spoke to David your father.

So Solomon built the house and finished it.

He built the walls of the house within with boards of cedar; from the floor of the house to the walls of the ceiling, he covered them on the inside with wood. He covered the floor of the house with cypress boards.

He built twenty cubits of the back part of the house with boards of cedar from the floor to the ceiling. He built this within, for an inner sanctuary, even for the most holy place.