Knob & Tube Replacement in Northern Virginia | Expert Installation

Challenge

The homeowners purchased a beautifully maintained 1925 colonial only to discover during renovation that the entire second floor and attic still had active knob-and-tube wiring buried under blown-in insulation. The insurance company refused to renew the policy, and the degraded cloth insulation was crumbling off the conductors in the attic, leaving bare wire resting against the insulation.

Solution

AJ Long Electric systematically replaced all K&T wiring over five days, fishing new 12-gauge Romex through the walls from attic and basement access points to minimize damage to the original plaster. We installed a new 200-amp panel, added AFCI protection on all bedroom and living area circuits, and ran dedicated 20-amp circuits for the kitchen and bathrooms.

Challenge

The owner of a 1935 row house in the Del Ray neighborhood needed to refinance but the lender's inspection found active knob-and-tube wiring in the attic and second floor. The ground-floor circuits had been updated in the 1980s, but the upper levels still relied on original K&T wiring with severely degraded rubber insulation. Budget constraints made a full rewire impractical.

Solution

We performed a targeted replacement of all active K&T circuits on the second floor and attic, replacing them with modern Romex copper wiring with grounding. The abandoned K&T on the first floor was verified as fully de-energized and labeled. We added GFCI protection in the bathroom and AFCI breakers for the bedrooms, and upgraded the fuse panel to a modern 150-amp breaker panel.

Challenge

The homeowner wanted to add blown-in insulation to improve energy efficiency but was told by two insulation contractors that they could not insulate over the active knob-and-tube wiring visible in the attic and exterior wall cavities. The home had a mix of original 1938 K&T wiring and some 1960s updates, creating a confusing patchwork that no one had fully mapped.

Solution

AJ Long Electric traced and mapped every circuit in the home, identifying which were K&T and which had been updated. We replaced all remaining active K&T circuits with modern Romex, routed through the attic and crawl space to minimize wall penetrations. The original fuse box was replaced with a 200-amp breaker panel with a detailed circuit directory.

Challenge

The new owners of a 4,800 sq ft historic estate were planning a major renovation and discovered that roughly 60% of the home still operated on original knob-and-tube wiring from 1920. The K&T circuits were overloaded with modern appliances, the cloth insulation had disintegrated in many locations, and previous owners had made dangerous splices connecting modern Romex directly to K&T wiring without proper junction boxes.

Solution

Working with the renovation contractor, AJ Long Electric performed a complete whole-house rewire during the renovation when walls were opened. We installed a 400-amp service with dual 200-amp panels to support the planned addition of a chef's kitchen, home theater, and geothermal HVAC system. Every circuit was designed to modern standards with dedicated circuits for all major appliances and AFCI/GFCI protection throughout.