Knob and Tube Wiring Replacement in Prescott Valley, AZ

If your home was built before 1950 and has never been rewired, there is a good chance knob and tube wiring is still active inside your walls, attic, and crawl space. This vintage wiring system uses rubber and cloth insulation that cracks and flakes with age, has no ground wire, and was never designed to handle the electrical load of a modern household. It is a documented fire hazard, and most insurance companies in Arizona now refuse to cover homes with active knob and tube wiring.

Assurance Electrical Services (ROC #322083) provides complete knob and tube removal, circuit rewiring, panel upgrades, and the insurance documentation you need to restore coverage. Call (928) 713-2177 for your free assessment.

Knob and Tube Wiring in Your Home? Don’t Wait.

Free on-site assessment · Insurance documentation included · Licensed electricians · ROC #322083

Or request a callback online → assuranceelectricalaz.com/contact

What Is Knob and Tube Wiring?

Knob and tube wiring was the standard residential electrical installation method from the 1880s through the 1940s. The system uses individual hot and neutral wires run separately through the framing with no ground wire. The insulation is rubber coated in cloth fabric, materials that were never designed to last a century.

Why Knob and Tube Wiring Is a Fire and Safety Hazard

  • Insulation failure: Rubber and cloth insulation hardens, cracks, and flakes after decades. What remains is often bare wire next to wood framing.
  • No ground wire: Without a ground conductor, these circuits cannot safely handle faults. Modern appliances with three-prong plugs require a ground to operate safely.
  • Undersized for modern loads: These circuits were designed for a few light fixtures and a radio, not today’s appliances and electronics.
  • Attic insulation risk: Blown-in insulation packed around active knob and tube wiring traps heat and creates conditions for a fire.

Is Knob and Tube Wiring Active in Your Home?

Many homeowners don’t know until an inspector, insurer, or electrician finds it. Our assessment documents exactly what’s active and what it will take to replace it.

Knob and Tube Wiring and Your Homeowner’s Insurance

Most major carriers in Arizona now either refuse to issue coverage for homes with active knob and tube wiring, or require its replacement as a condition of coverage. Some will issue a policy but exclude fire claims originating from the wiring. If you are buying, selling, or refinancing, this is a problem that must be addressed.

Assurance Electrical provides the specific documentation your insurance company needs: signed completion permits and county inspector sign-offs. We have been through this process hundreds of times and know exactly what carriers are looking for.

Our Replacement Process

  • Assessment: We trace every circuit, identify which are still active, and document the full scope.
  • Permits and planning: We pull permits and design the replacement layout.
  • Panel evaluation: If your panel needs upgrading, we include it in the project.
  • Wiring replacement: We remove active knob and tube and install modern grounded copper wiring.
  • GFCI and AFCI: All replacement circuits receive the protection required by current code.
  • Inspection and documentation: County inspection, signed permits, and insurance-ready reports.

Frequently Asked Questions

Full knob and tube replacement typically costs $8,000 to $15,000 for a complete home, depending on the number of active circuits, home size, and how accessible the wiring pathways are. Partial replacements targeting specific circuits or areas cost less. If a panel upgrade is required, that is typically $1,500 to $4,000 additional. The investment is offset by reduced insurance premiums, increased home value, and the elimination of an active fire hazard. Assurance Electrical provides detailed written estimates after on-site assessment — no obligation.

Most major carriers in Arizona either refuse to insure homes with active knob and tube wiring or require its removal as a condition of the policy. Some will issue a policy but exclude fire claims originating from the vintage wiring. Contact your insurer directly to confirm their requirements. Assurance Electrical provides the signed permits and county inspection documentation that satisfies insurance company verification.

The most reliable way is a professional electrical assessment. Visual indicators include ceramic insulators (knobs) stapled to exposed framing in the attic or basement, ceramic tubes where wire passes through joists, and cloth-wrapped wiring rather than the plastic-jacketed cable used since the 1960s. Many homeowners first discover it during a home purchase inspection or when an insurance carrier declines to renew their policy. If you’re unsure, we can assess your home and document exactly what’s there.

No. Knob and tube circuits cannot be extended, modified, or repaired under current NEC code — any alteration is a code violation. Damaged insulation cannot be restored. The system lacks a ground wire and cannot be made to meet modern grounding requirements without full replacement. The only code-compliant solution is complete removal and replacement of active circuits.

A full home replacement typically takes three to five days for an average-sized home, depending on the number of circuits, the accessibility of wiring pathways, and whether a panel upgrade is included in the project. Larger homes or those with limited attic and wall access may take longer. We’ll give you an accurate timeline as part of your written estimate.

Knob and tube wiring is not illegal to have in a home — it is illegal to modify, extend, or add to it under current NEC code. Having it does not automatically require immediate replacement by law, but insurance carriers, lenders, and buyers have effectively made replacement a practical necessity for homeowners who want to sell, refinance, or maintain coverage.

When we replace knob and tube wiring in an attic, we work through the insulation to access and remove the conductors. Disturbed insulation is consolidated and redistributed where possible. If significant insulation needs to be removed and replaced, we’ll note that in the project scope. Coordinating with an insulation contractor after rewiring is complete is common and straightforward — and once the knob and tube is gone, blown-in insulation is no longer a fire risk concern.