The IRC contains many important changes such as:

• An updated seismic map reflects the most conservative Seismic Design Category (SDC) based on any soil type and a new map reflects less conservative SDCs when Site Class A, B or D is applicable.
• The townhouse separation provisions now include options for using two separate fire-resistant-rated walls or a common wall.
• An emergency escape and rescue opening is no longer required in basement sleeping rooms where the dwelling has an automatic fire sprinkler system and the basement has a second means of egress or an emergency escape opening.
• The exemption for interconnection of smoke alarms in existing areas has been deleted.
• New girder/header tables have been revised to incorporate the use of #2 Southern Pine in lieu of #1 Southern Pine.
• New tables address alternative wood stud heights and the required number of full height studs in high wind areas.