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If you’re building a home or the time has come to replace your current breaker panel, you have some important decisions to make. The new breaker panel should be more than capable of handling your current electrical needs, with some room to grow. You never know what inventions will come into our lives or if you’ll someday change from a gas-powered appliance to electric.

The first two we need to answer when choosing a breaker panel:


  • How much power? A panel is sized by the amperage it can handle.
  • How many circuits? The size, layout, and types of major appliances determine how many different circuits are required (plus some empty circuit slots left for future use).
  • Then we need to ask ourselves what type of breaker panel is needed:
  • A standard main breaker panel, with a main breaker for disconnect
  • A sub-panel which is in addition to a main breaker elsewhere on the property 
  • A lug panel which is essentially a main breaker panel without a disconnect; the disconnect is at the meter instead
  • A transfer switch to go back and forth between the utility service and a standby generator

Electrical Service Amperage: 100, 125, 150, or 200 Amps?

Amperage simply indicates the maximum capacity of your electrical service. If you want to increase the amperage, the local utility needs to upgrade the service. Replacing the breaker panel alone will not increase the available power.

New homes almost always get built with 200 amps these days, and that’s the norm for upgrades, too. Smaller amperage is only recommended for very small single-family homes or an additional breaker panel such as for a bungalow or workshop on the property. In such cases, a load calculation will determine if 100, 125, or 150 amps is enough.

How Many Circuits on the Breaker Panel?

Most circuits provide power to one room’s outlets, switches, and overhead lights. Large rooms or rooms with lots of electronic devices may need two circuits. Major appliances run on 220/240-volt circuits so they need their own lines.

Concerned about too many appliances in one circuit? Add up the amps on each of the devices in the room. The formula for amps is watts divided by volts. So, an LED television that runs 70 watts on 110-volt power takes up .64 amps.

A standard 110-volt circuit provides up to 20-amp service. However, you don’t want to push it to the limit. Add up all those amps and make sure that your energy consumption will always stay a few amps below the 20-amp max.

Sub-Panels, Lug Panels, and Transfer Switches

Need to add a breaker panel for a guesthouse or other detached space? A sub-panel adds a new control panel and series of circuits without actually increasing the amount of power available (unless you also upgrade service at the meter).

Just need more circuits for the home? A replacement breaker panel may be the better option, especially if your current breaker panel is old, damaged, or has frayed wires.

Transfer switches are available with automatic settings, so that when a utility outage occurs the home automatically transfers to generator power and back when grid power is restored.

Whether you’ve added onto your home or your breaker panel has been damaged, we can help you select the right breaker panel based on your home and energy consumption. Talk to us today about installing or replacing circuit breakers and service panels or upgrading your electrical power!