I have a big house and worry I won’t be able to hear the alarm from the Keypad. Is there a way to link additional internal sirens within the home?

Yes. Honeywell Home offer a range of Wireless Doorbells that are compatible with the Keypad to extend the alarm sound within the home. The doorbell can be placed anywhere in the home, and when the alarm is triggered on the Keypad, the Doorbell will function as an additional internal siren by repeating the same alarm sound.