Ask an electrician in Washington, DC, Northern Virginia, or the Maryland suburbs for a "heavy-up" and they'll know exactly what you mean: increasing how much power your home's electrical service can safely deliver. Elsewhere in the country the same job goes by "service upgrade" or "service change." The classic heavy-up takes a house wired for 100 or 150 amps and rebuilds its service equipment to carry 200.
Key Takeaways
- "Heavy-up" is DMV (DC-Maryland-Virginia) regional slang for an electrical service upgrade, most commonly 100 or 150 amps to 200 amps.
- A 200-amp heavy-up costs $4,500-$8,500 in the DC area, with the permit and county inspection included.
- The on-site work is completed in a single day, with power off for roughly 4-8 hours.
- EV chargers, heat pump conversions, and home additions are the three most common reasons homes need a heavy-up.
- The job requires a county permit, a county inspection, and coordination with your utility -- Dominion Energy, Pepco, or BGE depending on where you live.
What Does "Heavy-Up" Mean?
A heavy-up replaces the equipment that brings power into your home -- the panel and breakers, usually the meter base, and often the service entrance conductors -- with heavier-capacity versions rated for more amperage. The name is regional shorthand for exactly that: "heavying up" the wires and gear so the house can draw more power. If a contractor from outside the DC area calls it a service upgrade, a service change, or a 200-amp upgrade, they are describing the same job.
Need a Panel Upgrade?
Outdated or overloaded electrical panels are a safety risk. Our team specializes in 200-amp upgrades throughout Northern Virginia, with same-day panel assessments available. Call (571) 444-6886 to get started.
A heavy-up is not the same as a like-for-like panel replacement. Swapping a failing 100-amp panel for a new 100-amp panel improves safety but adds no capacity. A heavy-up raises the service rating itself, which is why it also involves the meter equipment, the utility, and a new load calculation.
Why Do Homes Need a Heavy-Up?
Most homes in Fairfax, Vienna, Alexandria, Arlington, and the close-in Maryland suburbs were built between the 1950s and 1980s with 100- or 150-amp service -- plenty for the era's gas furnace, one window AC unit, and a modest kitchen. Today's demands are different:
- A Level 2 EV charger adds a dedicated 30-60 amp circuit
- Heat pumps and electric water heaters replace gas equipment
- Kitchen renovations add induction ranges, double ovens, and dedicated appliance circuits
- Finished basements, additions, home offices, hot tubs, and workshops all add load
When a load calculation shows the existing service can't absorb the new demand, the county won't approve the new circuit until the service is upgraded -- and that's when homeowners hear the word "heavy-up" for the first time.
What a Heavy-Up Includes
A complete 200-amp heavy-up typically covers:
- New 200-amp panel with copper bus and a full set of breakers, including AFCI/GFCI protection where code requires it
- New meter base rated for the higher amperage
- New service entrance conductors from the utility connection point to the panel
- Grounding and bonding brought up to current code -- ground rods, grounding electrode conductor, and bonding jumpers
- County permit and inspection, handled by the contractor
- Utility coordination for the disconnect and reconnect on installation day
- Circuit labeling and testing of every circuit before the crew leaves
When Is a Heavy-Up Required?
The most common triggers we see across Northern Virginia and suburban Maryland:
- EV charger installation: A 50-60 amp charging circuit rarely fits the load calculation on 100-amp service
- Heat pump or electric HVAC conversion: Replacing gas heat with electric often adds 40-60 amps of demand
- Home additions and major renovations: County plan review frequently requires a service upgrade as a condition of the building permit
- Hot tubs, saunas, and pool equipment: Large 240V loads on an already-full service
- Panel obsolescence: If a Federal Pacific or Zinsco panel has to go anyway, upgrading to 200 amps at the same time is far cheaper than doing two separate jobs
How Much Does a Heavy-Up Cost?
In the DC metro area, a 100- or 150-amp to 200-amp heavy-up runs $4,500-$8,500, including the permit and county inspection. Where you land in that range depends on the condition of the existing service entrance, whether the meter base needs relocation, panel accessibility, and how much correction the grounding system needs. Upgrades to 400-amp service -- for very large homes or two-EV households charging at full speed -- are quoted per project because utility transformer work can be involved.
Value Note: Because the crew is already rebuilding the panel, a heavy-up is the cheapest moment to add whole-house surge protection, an EV charger circuit, or a transfer switch for backup power. Adding them later means paying for separate trips and permits.
How Long Does a Heavy-Up Take?
The on-site work is a single day. A typical heavy-up starts between 8 and 9 AM, has power off for roughly 4-8 hours while the service equipment is replaced, and has the lights back on before the crew leaves that evening. Counting the estimate, permit, utility scheduling, and final inspection, the start-to-finish process usually spans two to four weeks.
Permits, Inspections, and Utility Coordination
Every heavy-up requires an electrical permit and a county inspection -- there is no legitimate way around it, and unpermitted service work creates real problems with insurance and resale. Your contractor should pull the permit and meet the inspector.
The utility side depends on where you live:
- Northern Virginia (Fairfax, Vienna, Alexandria, Arlington, Loudoun): Dominion Energy disconnects at the meter and reconnects after the work passes
- Montgomery County, MD: mostly Pepco territory, with its own scheduling process
- Prince George's County, MD: Pepco
- Anne Arundel County, MD: BGE
Your electrician coordinates the disconnect window so the outage lands on installation day, not before or after.
Heavy-Up Electrical Services in Alexandria, Fairfax, and Across the DMV
AJ Long Electric has been performing heavy-ups since 1996 -- 30 years of service upgrades in Alexandria, Fairfax, Vienna, Arlington, and Loudoun in Virginia, plus Montgomery, Prince George's, and Anne Arundel counties in Maryland and Washington, DC. We handle the load calculation, the permit, the utility scheduling, and the inspection, and we complete the swap in one day.
If you're weighing a heavy-up -- or a county reviewer or EV installer just told you that you need one -- our electrical panel upgrade services page covers the full scope, and our phones are answered 24/7 at (571) 444-6886.
