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Older Homes & Old Wiring

Federal Pacific, Zinsco and other problem panels, knob-and-tube and aluminum wiring, 2-prong outlets and surge protection for older California homes.

Older homes have a lot of character, and sometimes older wiring too. These guides cover problem panel brands, knob-and-tube and aluminum wiring, two-prong outlets and surge protection, without the scare tactics, so you can sort out what matters now and what can wait.

Guides in this section 5

Older Homes & Old Wiring

Federal Pacific, Zinsco and other problem panels: what to know

Federal Pacific Stab-Lok, Zinsco, Challenger, Pushmatic and Bulldog panels: which had recalls, which have problem histories, and when to replace.

Read guide Older Homes & Old Wiring

Knob-and-tube wiring: risks, insurance and replacement

What knob-and-tube wiring is, why it worries inspectors and insurers, how to tell if you have it, and how replacement works in older California homes.

Read guide Older Homes & Old Wiring

Aluminum wiring in 1960s and 70s homes

Why single-strand aluminum branch wiring from the 1960s and 70s is a fire concern, warning signs, and how electricians remediate it with COPALUM or AlumiConn.

Read guide Older Homes & Old Wiring

Two-prong outlets and cloth wiring: your GFCI options

Older homes with two-prong outlets and cloth-covered wiring: why a 3-prong outlet on ungrounded wire is a problem, the GFCI option, and adding a ground.

Read guide Older Homes & Old Wiring

Whole-home surge protection vs plug-in strips

How a whole-home surge protector at the panel works with plug-in surge strips, what it protects, grounding, and IES whole-home surge pricing.

Read guide

Helpful tools

Tool

Problem panel and recall checker

Check whether your electrical panel brand has a recall or a known problem history: Federal Pacific Stab-Lok, Zinsco, Challenger, Pushmatic, fuse boxes and more.

Open tool Tool

Can my panel handle it? (EV, heat pump, hot tub)

Quick, rough check of whether a 100 to 200 amp panel can handle a new EV charger, heat pump or hot tub, using a simplified NEC 220.82 load calculation.

Open tool

More sections

General information for California homes. Local rules and inspectors can vary. Not a substitute for an on-site inspection.