To choose a home distribution box, you must count your circuits and add 30% spare space. A distribution box, sometimes referred to as a panel board, distribution board, or breaker panel, is an essential part of electrical systems that makes it easier to distribute electricity throughout a structure. Dividing incoming electrical power from the main supply into subsidiary circuits is the. What size distribution box do you need for a house? How do you know which circuit breaker to use? Can you add more breakers later? Why do you need GFCI or AFCI breakers? Choosing the right size and setup for your distribution box keeps your electrical system safe and working well.