The Regular Padlock is a lock on the Main Door and the Garage Door. It is unlocked with the Padlock Key. When done so, the Regular Padlock will fall to the ground and the top plank will swing down, creating noise that alerts Granny.
The Top Plank has a similar appearance to the Bottom Plank except that it is thinner and has a padlock on the right side of it. Taking off the padlock will cause the plank to swing down, which will create a medium noise that will alert Granny.