Section R311.7.5.1, Riser height, of the IRC, is hereby amended by adding the following exceptions:
Section R311.7.5.1 Riser height exception 3 The dimension of the top and bottom riser of a stairway may vary up to 1-inch (25mm) from the stairway riser dimension; however, in no case shall the riser height exceed seven and three-quarter inches (196mm).
Section R311.7.5.1 Profile exception 4 The opening between adjacent treads is not limited on exterior stairs serving individual dwelling units.