Circuit breaker keeps tripping
We live in a newly constructed home for the past 6 years. One of the home's circuit breakers keeps tripping under the following scenarios:
1. Turning lights on/off
2. When an automatic iron that is plugged in turns on
3. When there is a thunderstorm with lightning (we will lose power to that part of the circuit)
The circuit according to what's written on the panel only has master bedroom lights and outlets plus all battery backed up (plastic disc shaped) smoke alarms in the home (about 7 of them). There are no other circuits, because everything else in the home appears to be fine. To my knowledge, smoke alarms do not draw that much current.
Could it be a faulty smoke alarm (drawing excessive amounts of current 7x24) or could it just be a bad circuit breaker?
I have a EE background, and can possibly try swapping out the circuit breaker with an identical one, or should I hire an electrician?
Your thoughts, comments will be gratefully appreciated!
Posting after a while or possibly my first post, lol, after all these years of reading excellent comments here ;) Thank you all.