Ezekiel 41:6

The side rooms were in three stories, one over another, and thirty in each story. They entered into the wall which belonged to the house for the side rooms all around, that they might be supported and not penetrate the wall of the house.

And the side chambers were three, one over another, and thirty in order; and they entered into the wall which was of the house for the side chambers round about, that they might have hold, but they had not hold in the wall of the house.