This is all Wisconsin says about lofts "(4) Exits from lofts.
SPS 321.03(4)(a)(a) At least one stairway exit shall be provided, to the floor below, for a loft exceeding 400 square feet in area.
SPS 321.03(4)(b) (b) At least one stairway or ladder exit shall be provided to the floor below for a loft, 400 square feet or less, in area. "
And egress "1. The nominal size of the net clear window opening shall be at least 20 inches by 24 inches irrespective of height or width. Nominal dimensions shall be determined by rounding up fractions of inches if they are ˝-inch or greater or rounding down fractions of inches if they are less than ˝-inch.
SPS 321.03(6)(b)2. 2. No portion of the window, including stops, stools, meeting rails and operator arms, shall infringe on the required opening. "