Ezekiel 41:7

And the breadth of the upper side [was made] according to the projection out of the wall, against the upper one round about the house, that it might be enlarged above, and that [men] might go up to the upper chambers from those below, and from the ground-sills to the third story.

And there was an enlarging, and a winding about still upward to the side chambers: for the winding about of the house went still upward round about the house: therefore the breadth of the house was still upward, and so increased from the lowest chamber to the highest by the midst.

The side rooms were wider on the higher levels, because the walls were narrower at the higher levels. Therefore the width of the house increased upward; and so one went up from the lowest level to the highest through the middle level.