Should I Rewire My Old House?

The honest decision guide -- including when patching is the right call.

Summary: Whether to rewire depends on wiring type (knob-and-tube usually rewire; modern Romex usually fine), condition (brittle/cracked = replace; intact = often okay), your plans (long-term residence + insurance concerns lean toward rewire), and budget. Partial rewires and pigtailing aluminum are valid middle-ground options.

The Wiring Types in Utah Homes

Knob-and-tube (pre-1950s):

  • Insulated wires through ceramic tubes and knobs
  • No ground conductor
  • Insulation: rubber/cloth, degrades over decades
  • Verdict: If still active, plan to rewire. Insurance companies increasingly refuse coverage.

Cloth-insulated copper (1940s-1960s):

  • Single conductors with cloth-and-rubber insulation
  • Insulation cracks and falls off with age
  • Verdict: Depends on condition. Some 70+ year installs are fine; others dangerous.

Aluminum branch wiring (1965-1973):

  • Solid aluminum for branch circuits (not just service entrance)
  • Aluminum expands/contracts more than copper -> loose connections
  • Verdict: Depends on whether outlets/switches are pigtailed with COPALUM or AlumiConn. Pigtailed: safe. Original devices unmodified: meaningfully dangerous.

Romex / NM cable (1960s-present):

  • Bundled cable: two conductors + ground in plastic jacket
  • Standard in every Utah home built after 1970
  • Verdict: Generally fine, even 40-50 years old, if protected from heat and rodents.

When Patching Is the Right Call

  • Modern Romex/NM in good condition, only one specific repair needed
  • Aluminum wiring already pigtailed at every device
  • Cloth-insulated wiring in good condition AND insurance accepts it AND no major electrical load additions planned
  • Home you're selling within 2-3 years AND wiring isn't actively unsafe (disclose to buyer)
  • Budget genuinely can't allow full rewire -- address worst circuits first

When Rewiring Is the Right Call

  • Active knob-and-tube anywhere in the home
  • Cloth-insulated wiring is brittle, cracked, or exposed
  • Aluminum branch wiring not pigtailed
  • Multiple circuits overloaded (tripping breakers, warm outlets, dimming lights)
  • Insurance has refused or non-renewed policy due to wiring
  • Major remodel anyway -- walls open is the cheapest time to rewire
  • Long-term residence with safety + insurance peace of mind goals
  • Adding significant load (panel upgrade, EVs, hot tub, central AC, generator, solar)

What a Rewire Costs in Utah

  • Under 1,200 sq ft: $7,500 - $14,000
  • 1,200-1,800 sq ft: $11,000 - $20,000
  • 1,800-2,500 sq ft: $16,000 - $28,000
  • 2,500-3,500 sq ft: $22,000 - $38,000
  • 3,500+ sq ft older custom: $30,000+

Partial rewires (one floor, kitchen-only): $4,000-$12,000.

Pigtailing aluminum (no full rewire): $35-$75 per device. ~$3,500-$7,500 for a 100-device home.

What's Involved in a Rewire

  1. Free in-home assessment (1-2 hours)
  2. Permits with the city
  3. Tear-out of old wiring (1-3 days)
  4. Pull new circuits (3-7 days)
  5. Install boxes, outlets, switches, fixtures (2-4 days)
  6. Panel upgrade if needed (1-2 days)
  7. Rough inspection by city
  8. Drywall patching (by drywall contractor, separate scope)
  9. Final inspection
  10. Cleanup + walkthrough

Typical timeline: 2-4 weeks of electrical work, plus drywall and paint.

The "Rewire During Remodel" Sweet Spot

If you're already remodeling a kitchen, bathroom, basement, or addition -- rewire that area during the remodel. Walls are open, drywall contractor is on site, marginal cost of new wiring is a fraction of doing it later.

FAQ

Will my insurance company drop me for knob-and-tube?

Increasingly yes. Many carriers now require K&T removal as a condition of coverage. Some grandfather existing policies but won't renew.

Can I rewire just part of the house?

Yes -- partial rewires are common. We focus on the highest-risk areas first.

Can you rewire without tearing out drywall?

Sometimes -- fishing wire through finished walls works for shorter runs. Full home rewires usually require some drywall removal.

How disruptive is a rewire?

Most homeowners stay in the home. Power is cycled circuit-by-circuit, not whole-home for long periods. Dust and minor drywall damage are unavoidable.

Need a Rewire Assessment?

Free in-home assessment. We'll tell you straight -- rewire, partial, or just patch.

801-885-4521
Call Now: (801) 885-4521