Today, the lines between electric sub-panel and all five GFCIs (Ground-Fault Circuit Interrupter) are hot (with live electricity). These five GFCIs will then take load from Mud Room, Bath, Master Bedroom, Exhaust Hood and Outdoor and crawl space lights respectively. This way, the electric sub-panel can be closed.
Working on each above mentioned individual area can then be done by just opening the its relative circuit breaker. Pretty convenient and safe this way.
Since the addition is with live electricity, I also installed a temporary fire alarm at the very top of the inside roof. It will be taken down when doing the insulation and drywall. After all finish, it will place at the top of ceiling instead.
Tomorrow, I will take a break on electric work and working on telephone land line & cable outlet in our addition.