KJV
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.
BSB
The side rooms surrounding the temple widened at each successive level, because the structure surrounding the temple ascended by stages corresponding to the narrowing of the temple wall as it rose upward. And so a stairway went up from the lowest story to the highest, through the middle one.