Outdated Wiring Replaced With Modern Safety Standards
Knob and Tube Rewiring in Missoula for homes with exposed porcelain insulators and cloth-wrapped conductors
Edison Electric performs knob and tube rewiring for homeowners who are dealing with electrical systems installed before 1950. You might notice ceramic knobs mounted along floor joists in your basement or attic, or cloth-covered wiring running through open cavities without grounding conductors. This type of wiring was installed when electrical demand was a fraction of what modern appliances and devices require, and it lacks the capacity and grounding necessary to meet current safety codes.
The rewiring process involves removing the old knob and tube conductors and installing a grounded electrical system with modern circuit breakers, insulated wiring, and properly sized conductors. This work is common in older neighborhoods across Missoula, where homes still carry original electrical infrastructure that was never updated during renovations. Insurers often flag these systems during underwriting reviews, and lenders may require replacement before closing on a mortgage.
If you are buying or refinancing a home with knob and tube wiring, reach out to discuss what the replacement process looks like for your property and timeline.
How the System Is Replaced Without Full Wall Demolition
You will see Edison Electric open selective access points in walls and ceilings to route new Romex cable through existing cavities. The crew maps out the current circuit layout, shuts off power at the main panel, and removes energized knob and tube wiring while marking which outlets and fixtures are tied to each run. Where runs are inaccessible without opening drywall, small patches are cut, new wire is fished through, and access points are repaired after final connections are made.
After installation, you will have a grounded three-prong outlet system, updated circuit protection at the panel, and wiring that can support air conditioning units, electric ranges, and other high-draw appliances. The system will be brought up to the National Electrical Code, which means it will include proper conductor sizing, grounding paths, and overcurrent protection. Your outlets will no longer spark when plugging in devices, and breakers will trip appropriately when circuits are overloaded instead of relying on aging fuses or unprotected conductors.
The scope varies based on how much of the original system is still active, whether the panel has already been updated, and what level of access exists in finished spaces. Edison Electric does not perform cosmetic drywall finishing beyond patching opened sections, so you may need to coordinate painting or texturing separately after electrical rough-in is inspected and approved.
Common Questions About Replacing Old Electrical Systems
Homeowners often ask how long the work takes, whether the entire house needs to be rewired at once, and what happens if wiring is found inside walls that cannot be accessed without significant demolition.
What does knob and tube wiring look like in an attic or crawlspace?
You will see white porcelain knobs nailed to framing members with individual black and white conductors running between them, separated by air gaps instead of being bundled in a cable jacket.
How long does a full rewire take in a typical Missoula home?
Most single-story homes under 1,500 square feet take three to five days depending on wall access, panel location, and whether the basement or attic provides open routing paths.
Why do insurance companies require knob and tube systems to be removed?
Cloth insulation degrades over time, connections can loosen at splice points, and the system lacks grounding, which increases the risk of shock and fire when used with modern electrical loads.
What happens to the old wiring after new circuits are installed?
The knob and tube conductors are disconnected at the panel and at each junction point, then left in place if they are not creating a hazard or accessible for removal without damaging finished surfaces.
When is a service panel upgrade required during rewiring?
If your current panel uses fuses or does not have enough available slots for new branch circuits, Edison Electric will replace it with a breaker panel rated for the updated electrical load.
If your home inspector flagged knob and tube wiring or your insurer has sent a notice requiring replacement, contact Edison Electric to schedule a walkthrough and get a detailed scope based on what is still active in your home.
