Panel Upgrades in Frederick, Maryland
200-amp upgrades, heavy-ups, sub-panels, and Federal Pacific & Zinsco replacements - done to code and inspected.
DC Electrical Contractor #EM-40-0001168 · MD Master Electrician #7987 · VA Class A Contractor #2705198087 · EPA & OSHA Certified

Pirro Electric handles panel upgrades for homeowners, businesses, and property managers in Frederick, MD. Work is scoped on site, quoted in writing, permitted, and inspected before we call it done. Typical scope: 100-amp to 200-amp service upgrades ("heavy-ups"), federal pacific stab-lok panel replacement, and zinsco panel replacement.
Frederick's downtown historic district is full of 19th-century rowhomes with knob-and-tube remnants, undersized services, and old fuse boxes - work that requires permit coordination with the Historic Preservation Commission. Newer subdivisions on the east side need mostly EV chargers and panel replacements.
When You Actually Need a Panel Upgrade
A 'heavy-up' - moving from 100-amp to 200-amp service - is one of the most common requests we get. You typically need one if you're adding an EV charger, a heat pump or mini-split, a hot tub, an addition, or if your existing panel is full and there's no room for new circuits.
If your panel is a Federal Pacific Stab-Lok or a Zinsco, the answer is simpler: replace it. Both panels have documented histories of breakers failing to trip during overcurrent - a known fire hazard and one that most insurers now flag during inspection.
Why Pirro Electric for Panel Work
Panel work is some of the highest-stakes residential electrical you can hire out - bad workmanship can quietly create fire hazards for years. We're licensed master electricians in MD, DC, and VA, fully insured, and we pull permits on every panel swap. No exceptions.
More detail on scope and pricing: our full panel upgrades & heavy-ups page or the electrical panel upgrade cost in the dmv guide.
What Affects the Price of Panel Upgrades & Heavy-Ups in Frederick
Every quote is written after an on-site look. These are the variables that move the number:
- Service size (100A → 200A vs. 200A → 400A)
- Overhead vs. underground service drop
- Meter base and service entrance condition
- Panel location (basement vs. exterior wall)
- Permit and county inspection fees
- Whether your current grounding system needs upgrades
Common Panel Upgrades & Heavy-Ups Projects in Frederick
- Historic home rewiring with HPC coordination
- Service upgrades on 1900s rowhomes
Neighborhoods servedDowntown Frederick · Worman's Mill · Spring Ridge · Clover Hill
ZIP codes21701 · 21702 · 21703 · 21704
What's Included
Every job in Frederick comes scoped, permitted, and inspected - no shortcuts.
- 100-amp to 200-amp service upgrades ("heavy-ups")
- Federal Pacific Stab-Lok panel replacement
- Zinsco panel replacement
- Main breaker panel and meter base swaps
- Sub-panel installation for additions and detached structures
- Whole-home surge protection at the panel
- Panel relabeling and circuit mapping
- AFCI and GFCI breaker upgrades
Panel Upgrades & Heavy-Ups in Frederick - Common Questions
What Customers Say
Excerpts from verified Google reviews of Pirro Electric.
"We use Pirro across our portfolio of 50+ commercial retail buildings. Excellent work, responsive, priced competitively, and they get it right the first time."
Timothy M.
Google Review · Commercial Property Manager"Pirro re-wired my whole townhouse, updated the panel, and replaced every outlet and switch. Professional, friendly, and on time. Couldn't ask for a better company."
JMW
Google Review · Verified Homeowner"If you're thinking of going with Pirro - do it. You won't be sorry. I run a medium-sized HOA and wouldn't use any other company for our electric."
Amanda S.
Google Review · HOA Board DirectorNearby Areas We Serve
Same panel upgrades & heavy-ups crew, next town over.
Related Services in Frederick
Often booked alongside panel upgrades & heavy-ups.
Ready to Get Started in Frederick?
Free written quotes. Licensed & insured. Same-week scheduling for most projects.