About Siri and HomeKit:
Siri can make it easy to execute sophisticated operations with a single statement. Siri recognizes Home, Room, and Zone names and can support statements like:
“Siri, lock up my house in Tahoe”
“Siri, turn off the upstairs lights”
“Siri, make it warmer in the media room”
Siri also recognizes accessory names and characteristics, so that you can make statements like “Siri, dim the desk lamp.”
For more information, please visit Apples FAQ here.