Electrical Sub Panel Installation

electrical panel upgrade

Electric Sub Panel Change or Installation is a Job for the Experts

Whenever a home or business owner needs to add extra circuit capacity to an existing electrical panel, the best course of action is to call a professional electrician. An electric sub panel is connected to the main electric panel, provided the main panel does not need replacing, and it makes powering the new addition more straightforward. It is a complex process and several factors need to be taken into consideration to make sure the job is done correctly, safely. Our Northern Virginia electricians have a quarter of a century of experience in electric sub panel change or installation, and we always put our customers’ safety and satisfaction first.

Should I add a sub panel or upgrade main panel?

The decision to add a subpanel or upgrade the main panel depends on several factors. Without a thorough assessment of your specific electrical system and needs, it's challenging to provide a definitive answer. However, we can offer some general guidance:

  1. Electrical Load: Consider the current and future electrical load requirements of your home. If your main panel is already approaching its capacity due to additional appliances, electronics, or home additions, upgrading the main panel may be necessary.
  2. Available Space: Check if you have sufficient space in your existing main panel to accommodate new circuit breakers for additional circuits. If space is limited, adding a subpanel might be a more feasible solution.
  3. Cost: The cost of adding a subpanel may be less than upgrading the main panel.
  4. Convenience: Subpanels can be beneficial if you have a specific area of your home, like a new addition, workshop, or basement, that requires its own circuits. This way, you can distribute the electrical load more effectively.
  5. Future Expansion: If you anticipate further expansions or additions to your property, planning for a larger main panel upgrade could save you from needing multiple subpanels in the future.
  6. Safety and Code Compliance: Ensure that any electrical modifications adhere to local building codes and safety standards. A qualified electrician can guide you through the appropriate options that meet the regulations.

In any case, we strongly recommend consulting a licensed electrician who can perform an in-person assessment of your electrical system and provide personalized recommendations based on your specific needs. They will be able to offer you the most accurate advice and ensure that your electrical system is safe and up to code.

Why Would I Need an Electric Sub Panel Change or Installation?

An electric sub panel provides an extension of electrical service from the main electric panel in the home or office. These are particularly useful where a large amount of energy is needed away from the main building: in finished basements with entertainment systems or wet bars, detached garages or workshops, or new additions to a home or office. An electric sub panel installation may also be required outdoors for hot tubs or other spa equipment, yard equipment or other high-powered industrial or commercial equipment. Naturally, an electric sub panel change may be required if you already have one, but it is not functioning properly.

Three Important Things to Understand about an Electric Sub Panel Installation:

  • An electric sub panel change does not add more electrical power coming into a home or office; it does, however, provide more efficient and easy-to-manage electrical service running from the main electric panel to other areas of the home.
  • Installing an electric sub panel helps when there is not enough space for extra circuit breakers within the main electric panel to handle the extended electrical needs of the home or business. An electric sub panel installation creates extra room for new circuit breakers in a separate physical location.
  • An electric sub panel change or installation clarifies and simplifies the electrical service in a home or office by providing an electric panel for separate physical areas that need heavy doses of electric service, such as a kitchen, a workshop, a home office, garage or basement.

Root Electric installed 2 sub panels in our home. Bill was super helpful during the initial visit and was responsive to my follow up questions. Installation was professional, super smooth, efficient and done to a high standard. Would highly recommend Bill and his team to anyone needing a trustworthy master electrician to help with their project.

Paul Keeton

How much does it cost to install an electrical sub panel?

Here are some general considerations that can affect the cost of installing an electrical subpanel:

  1. Type and Capacity of Subpanel: The cost will vary based on the type and amperage capacity of the subpanel you choose. Larger capacity subpanels with more circuits will generally be more expensive.
  2. Labor and Complexity: The complexity of the installation and the amount of labor required will impact the overall cost. If the installation involves a lot of wiring, conduit runs, or modifications to the existing electrical system, the cost may be higher.
  3. Permits and Inspections: Depending on your local regulations, obtaining permits for the installation may be necessary. This can add to the overall cost, as there might be permit fees involved.
  4. Distance and Accessibility: If the subpanel needs to be installed at a considerable distance from the main panel or if the installation location is hard to access, it may increase labor costs.
  5. Material Quality: The quality of the subpanel, wiring, and circuit breakers can influence the cost. Higher-quality materials may have a higher upfront cost but can offer better performance and longevity.
  6. Existing Electrical System Condition: If the existing electrical system requires upgrades or repairs to support the subpanel installation, these additional tasks may contribute to the overall cost.
  7. Location: Regional differences in labor rates and material costs can impact the overall installation cost.
  8. Electrician's Experience: The expertise and reputation of the electrician or electrical contractor you choose can also affect the cost. Experienced professionals may charge higher rates but can offer greater reliability and quality work.
  9. Additional Features: If you require special features in the subpanel, such as surge protection, GFCI breakers, or specific types of circuit breakers, these extras will add to the overall cost.

Remember that installing an electrical subpanel is not a DIY project and should be carried out by a licensed electrician. They will assess your electrical needs, consider these factors, and provide you with a detailed quote based on your specific requirements and the local regulations. Always prioritize safety and quality when it comes to electrical work.

Where do you put a subpanel?

The location of a subpanel depends on the specific needs and requirements of your electrical system and the intended purpose of the subpanel. Here are some common locations where you might install a subpanel:

  1. Near the Main Panel: Subpanels are often installed in close proximity to the main electrical panel. This can make wiring and connections more straightforward and minimize the length of the feeder cable running from the main panel to the subpanel.
  2. Garage: Subpanels are commonly installed in garages, especially if you plan to use the garage as a workshop or have additional electrical loads like power tools or electric vehicle charging stations.
  3. Basement: If your home has a basement, it's a convenient location for a subpanel. Basements are frequently used for laundry rooms, home theaters, or other areas that may require additional electrical circuits.
  4. Attic: Attics can be suitable locations for subpanels, especially if you're adding living space or converting the attic into a bedroom or office.
  5. Additions or Renovations: If you're adding an extension to your home or renovating a particular area, a subpanel might be installed in that new space to accommodate the increased electrical demands.
  6. Outbuildings: Subpanels are often placed in outbuildings like sheds, barns, or workshops to provide power for equipment and lighting.
  7. Pool or Spa Area: If you have a pool or spa, a subpanel near this area can supply electricity for pool pumps, heaters, and lighting.

When choosing a location for your subpanel, consider the following factors:

  • Accessibility: The subpanel should be easily accessible for maintenance and troubleshooting. Avoid placing it in areas that are hard to reach or obstructed by furniture or equipment.
  • Space: Ensure there's enough space to accommodate the subpanel and the necessary clearances required by local electrical codes.
  • Ventilation: If the subpanel generates heat, proper ventilation should be considered to prevent overheating.
  • Protection: Consider protecting the subpanel from potential physical damage or exposure to the elements, depending on the installation location.

Always consult with a licensed electrician to determine the most appropriate location for your subpanel. They will assess your specific electrical needs and provide professional guidance to ensure a safe and compliant installation.

How many circuits can you put on a sub panel?

The number of circuits you can put on a subpanel depends on the amperage capacity of the subpanel and the individual circuit breaker sizes used. A subpanel typically comes with a main breaker that serves as the panel's overall capacity limit. The total amperage rating of all the circuit breakers in the subpanel should not exceed this main breaker's rating.

Here are some common examples of subpanel capacities and the maximum number of circuits you can typically have based on standard circuit breaker sizes:

  1. 100-Amp Subpanel: With 100-amp main breaker capacity, you can have approximately 20 to 24 circuits using 15-amp breakers or 12 to 16 circuits using 20-amp breakers.

  2. 125-Amp Subpanel: A 125-amp main breaker capacity allows for around 24 to 30 circuits with 15-amp breakers or 16 to 20 circuits with 20-amp breakers.

  3. 200-Amp Subpanel: With a 200-amp main breaker capacity, you can have approximately 40 to 48 circuits using 15-amp breakers or 26 to 32 circuits using 20-amp breakers.

Keep in mind that the above numbers are general estimates, and the actual number of circuits may vary depending on the specific subpanel model and the combination of circuit breaker sizes you use.

It's important to consult with a licensed electrician when planning the installation of a subpanel. They will calculate the electrical load requirements of your home and recommend the appropriate subpanel size and breaker combination to meet your needs safely and in compliance with local electrical codes. Proper planning ensures that you have enough circuits for your current and future electrical demands while staying within the subpanel's capacity limits.

Do I need a main breaker in a sub panel?

Yes, a main breaker is required in a subpanel. The main breaker serves as the disconnecting means for the subpanel, allowing you to shut off all power to the subpanel circuits in case of an emergency or for maintenance purposes. It acts as a safety feature, enabling you to isolate the subpanel from the main electrical service.

The main breaker in a subpanel is different from the main breaker in your main electrical panel (also known as the service panel or distribution panel). The main breaker in the main panel controls the power supply to the entire electrical system of your home, while the main breaker in the subpanel controls the power supply to the circuits connected to that subpanel.

When installing a subpanel, the main breaker in the subpanel should be sized to match the capacity of the subpanel and the feeder wire that connects it to the main panel. The main breaker rating of the subpanel determines the maximum amount of current the subpanel can handle, ensuring that it does not exceed the capacity of the feeder and the main panel.

For example, if you have a 100-amp subpanel, the main breaker in the subpanel should be rated for 100 amps. This means the total current flowing through the subpanel should not exceed 100 amps to avoid overloading the subpanel and its feeder.

Always have a licensed electrician handle the installation of a subpanel and ensure that it is done correctly, adhering to local electrical codes and safety standards. The electrician will size the main breaker appropriately and make sure the subpanel installation is safe and compliant.

Customer Testimonial

Bill Root came to my house to provide a free estimate to replace our electrical panel. During the home inspection as we were purchasing our new home, our home inspector raised safety concerns. Bill made an honest assessment and recommended there was no need to change the panel and that the home inspector was only bringing the issue to my attention. I appreciated his honesty.

Erin J.
Arlington, VA

Other Important Electric Sub Panel Change Details:

  • The size of the sub panel depends on the application. For example, backyard sheds or finished basements generally need a small sub panel in the 30 to 60 amps range. This covers needs of yard equipment, light power tools, leaf blowers, portable saws, home entertainment systems or wet bars.
  • Detached garages, heavy duty workshops or pool houses usually need more power. In that case, we would install sub panels in the 60-100 amp range. This powers higher-demand equipment such as compressors, welders, air conditioners, post lifts, spa equipment, etc.
  • Therefore, an electric sub panel installation can be configured anywhere from 30 amps, 240 volts up to 100 amps, 240 volts.

For safety and quality reasons, electric sub panel change or installation should always be done by a professional electrician. Here at Root Electric, we can get the job done right the first time and always ensure your safety.

Call us at (703) 494- 3989 today if you are expanding your home or office and need an electric sub panel installation!


Satisfaction / Safety First Since 1986