Knob-and-Tube Wiring

In a condo or TIC, wiring that serves one home may pass through common walls or shared equipment. Learn which documents and electrical facts determine approval, access, permits, restoration, and responsibility for the cost.

A glowing power-strip light does not prove effective surge protection on an ungrounded outlet. This guide explains equipment grounding, GFCI limitations, whole-house surge devices, and a safer layered plan for electronics.

Most smart switches need wiring that an old switch box may not contain. Learn how neutral wires, equipment grounding, lamp compatibility, brittle insulation, and three-way circuits determine whether a device swap is safe.

San Francisco’s all-electric requirement does not apply to every remodel. See how the City defines a Major Renovation and why older homes need early planning for service capacity, new appliance circuits, and active knob-and-tube wiring.

An old knob-and-tube circuit is not automatically unlawful just because a newer code exists. This guide separates existing wiring from new work and explains when safety, insulation, remodeling, permits, or insurance require a closer look.

BayREN’s limited-time 2026 incentive may provide up to $2,000 for active knob-and-tube remediation or $300 for certification that old wiring is inactive. Learn how EASE Home eligibility, inspection, documentation, and project timing fit together.

Selling a San Francisco home with knob-and-tube wiring does not always require a complete rewire before listing. Learn what sellers should disclose, when replacement may improve the transaction, how insurance and buyer financing affect the decision, and what documentation can reduce uncertainty during escrow.

Buying an older home with knob-and-tube wiring does not automatically mean walking away—but it does require more due diligence than a standard home inspection. Learn what to verify, which documents to request, how to evaluate insurance and rewiring costs, and how to structure your offer before taking on an electrical system you do not fully understand.

Replacing only part of a knob-and-tube wiring system can seem like an attractive way to reduce costs and minimize disruption. In some situations, it’s a practical solution—but in others, it simply postpones a larger electrical upgrade. This guide explains when partial replacement makes sense, the hidden challenges of mixed wiring systems, and how electricians evaluate whether a targeted upgrade or a full rewire is the better long-term investment.

Planning to insulate the attic in an older San Francisco home? If active knob-and-tube wiring is still present, adding insulation may not be as simple as it seems. This guide explains why older wiring depends on open-air cooling, how insulation affects electrical safety, and what options homeowners have before moving forward with energy-efficiency upgrades.