Section 419.1, General, of the IBC, is hereby amended by deleting the exception and inserting in lieu thereof the following two exceptions:
Section 419.1 General. Exceptions:
1. Dwelling or sleeping units that include an office that is less than 10 percent of the area of the dwelling unit are permitted to be classified as dwelling units with accessory occupancies in accordance with Section 508.2.
2. Detached one - and two - family dwellings and townhouses that include an office that is less than 20 percent of the area of the dwelling unit and constructed in accordance with the International Residential Code.