
Complete Guide to Electrical Panel Upgrades in Northern Virginia
Everything Northern Virginia homeowners need to know about electrical panel upgrades, including signs you need one,...

Property-specific electrical panel replacement and service-capacity planning, with load calculations, utility coordination, labeling, and permit-path confirmation. Trusted by homeowners throughout Montgomery County since 1996.
An electrical panel project should start with the condition of the existing equipment and the loads the home needs to support. AJ Long Electric documents the panel, service conductors, grounding and bonding, breaker configuration, available space, and visible signs of heat or damage. A load calculation helps determine whether the project calls for a like-for-like replacement, additional distribution capacity, or a service upgrade. When the scope affects utility-owned equipment, the meter, or service conductors, that coordination is identified before scheduling. The written proposal separates panel work from optional surge protection, branch-circuit corrections, finish work, and other conditions that cannot be confirmed until the system is evaluated. For a Kensington property, the recommendation follows the actual equipment, access, electrical capacity, and project goals documented during the assessment.
Kensington packs more genuinely old housing into half a square mile than anywhere else in Montgomery County: 1880s-1900s railroad-suburb Victorians along the original B&O commuter line, 1910s-20s Craftsman bungalows, and 1950s-60s brick capes filling in around them. A panel upgrade in the historic core is really a modernization of a century of layered electrical work.
AJ Long Electric defines the panel replacements & upgrades scope for the individual Kensington address. The written proposal identifies known conditions, access assumptions, included electrical work, exclusions, and any coordination that must be confirmed before scheduling. Before work begins, we confirm whether the defined scope requires coordination with the Montgomery County Department of Permitting Services; permit, inspection, and utility responsibilities are stated in the proposal for the address.
In Old Town Kensington's Victorian-era homes we routinely find 60-amp fuse panels, ungrounded two-wire circuits, and knob-and-tube that's sometimes still energized in attic and basement runs — often buried under generations of incremental patches that make circuits hard to trace, which is exactly why we map what's actually feeding the panel before we replace it. There's a permitting layer, too: the electrical permit runs through Montgomery County DPS, but visible exterior service changes in the Kensington historic district — a relocated mast, meter, or riser — can additionally trigger Montgomery County Historic Area Work Permit review, which we account for up front rather than mid-job. The 1950s-60s capes and ranchers in Rock Creek Hills and Parkwood are a more conventional 100-to-200-amp story, though that era's Federal Pacific and Zinsco equipment gets replaced outright when we find it. The upgrade runs $3,500-$7,500, Kensington is on the Pepco grid, and we coordinate the meter pull.

Our licensed electricians serving Montgomery County
AJ Long Electric documents the existing system before recommending panel capacity or equipment. The written scope distinguishes confirmed work from conditions that require access, utility input, or authority review, giving the homeowner a clearer basis for the decision.
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The proposed panel and service size follow a load calculation and the home's planned electrical use.
Circuit organization and labeling make the system easier to operate and maintain.
Visible damage, incompatible components, crowded wiring, grounding, and service-equipment conditions are addressed in the proposal.
Utility, permit, inspection, and outage requirements are confirmed for the address and defined work.
Future EV charging, HVAC, kitchen, or addition loads can be considered during design.
For panel replacements & upgrades at this Kensington property, AJ Long Electric begins by reviewing the requested outcome, relevant equipment, safe access, and observed electrical conditions. The written proposal identifies the defined work, sequencing, coordination responsibilities, and exclusions. Authorized work is tested and documented to the completed scope; newly exposed conditions are discussed before the scope changes.
| Typical cost in Kensington | $3,500-$7,500 (200A); 400A quoted per projectThe written estimate follows the defined equipment, access, routing, and coordination scope. |
|---|---|
| Typical timeline | 1 day on site |
| Permit authority | Montgomery County Department of Permitting ServicesAJ Long Electric confirms the permit and inspection path for the address and states the included coordination in the written proposal. |
| Applicable code standard | NEC Article 408 & 250service equipment, panelboards, grounding & bonding (National Electrical Code, NFPA 70). |
| Most common local condition | Property-specific equipment, access, and electrical conditions are confirmed during the assessment. |
Permit fees, scope, and existing-condition surprises affect final pricing. Verify current requirements with the Montgomery County Department of Permitting Services and review the NFPA 70 (National Electrical Code).
We document the panel, service equipment, loads, grounding, breaker configuration, and visible conditions.
The recommended capacity and equipment follow the existing and planned electrical demand.
The estimate identifies included equipment, corrections, coordination, access, and exclusions.
Permit, inspection, outage, and utility requirements are confirmed for the address.
The approved equipment is installed, terminated, grounded, bonded, and labeled to the defined scope.
Connections and operation are checked, the directory is reviewed, and applicable closeout steps are completed.
The exact scope depends on the existing service and the load calculation. It may include the panel enclosure, breakers, grounding and bonding corrections, service conductors or meter equipment, labeling, utility coordination, and required inspection work.
We use the home's existing and planned loads, equipment ratings, service configuration, and the applicable calculation method. A larger rating is not automatically the correct answer for every property.
Brand and age alone do not describe the complete condition. A licensed electrician should identify the exact equipment and evaluate damage, breaker compatibility, service capacity, grounding, and the homeowner's planned loads before recommending a scope.
That depends on the service configuration and work boundary. When utility disconnect, meter, or service-entrance coordination is needed, it is identified and scheduled as part of the project plan.
Permit and inspection requirements depend on the address and defined scope. AJ Long Electric confirms the authority and coordination path before work begins.
The equipment, electrical capacity, access, property layout, and local authority can change the scope from one Kensington address to another. AJ Long Electric confirms those conditions and the applicable coordination path before finalizing the proposal.
Cost depends on the equipment, electrical capacity, access, route, corrective work, and local coordination required at the property. AJ Long Electric provides a written estimate after the relevant conditions and project boundary are assessed.
Permit and inspection requirements depend on the address and the defined electrical scope. AJ Long Electric confirms the applicable path with the authority serving the property and states the included coordination in the written proposal.
Timing depends on the defined scope, safe access, equipment and material availability, property conditions, and any permit, inspection, utility, or other-trade coordination. AJ Long Electric confirms the anticipated sequence after the assessment.
AJ Long Electric has served the region since 1996. We are a licensed, insured electrical contractor led by a master electrician, and we define the scope, access assumptions, exclusions, and project-specific coordination before authorized work begins.
Scheduling depends on the current workload and the project scope. Call (571) 444-6886 or request an appointment online and we will confirm the earliest available time for your Kensington address.
It can. The electrical permit itself always runs through Montgomery County DPS, but if the upgrade changes the home's visible exterior — a relocated service mast, meter, or riser on a historic-district street — Montgomery County Historic Area Work Permit review can apply on top of it. AJ Long Electric identifies whether your address triggers the extra review and sequences both approvals, so the 200-amp upgrade ($3,500-$7,500) isn't stalled by a permitting surprise.
The panel upgrade is the foundation, not the whole fix. Replacing a 60-amp fuse panel with 200-amp service ($3,500-$7,500) modernizes the service equipment, but knob-and-tube still energized in attic or basement runs needs to be traced and remediated circuit by circuit. AJ Long Electric maps what actually feeds the panel in these 1880s-1920s homes, replaces the live knob-and-tube sections we find, and permits everything through Montgomery County DPS with the Pepco meter pull coordinated.
Typical Price Range: $3,500-$7,500 (200A); 400A quoted per project
Contact AJ Long Electric to request a written estimate for the defined Kensington scope.
We also provide professional panel replacements & upgrades services in these nearby communities.
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