Your units conversions are just wrong - or at best, approximate. Certainly not accurate to three decimal places of feet.
193.5 in is not 16.25ft, but 16ft 1 1/2 inches, or 16.125 ft.
167 3/4 in is not 14ft, but 13ft 11 3/4 in or 13.9792 ft.
If you are working in Imperial units, why are you not using either Architectural (Feet, inches and fractions) or Fractional units (inches and fractions)?
What you have drawn is not what your text says - and as DaveR’s diagram shows.
The bottoms of your windows are 1’6 1/4" above the floor, 5’4 3/4" high, and another 1’1" to the ceiling - total, 8ft.
You want the windows 2ft = 24in above the floor. What height did you want the windows themselves then?
You sound unfamiliar with imperial units, if you were surprised that 20’ = 240".
Why is the corner of the room not at the origin?