Rewiring an Old House: What St. Louis Homeowners Should Know

St. Louis is full of beautiful older homes: craftsman bungalows in Webster Groves, Victorian gems in Lafayette Square, mid-century ranches throughout the county. But older homes often have older wiring that may be inadequate or unsafe for modern electrical demands.

Here's what you need to know about rewiring.

Signs Your Home May Need Rewiring

Frequent Electrical Problems

• Breakers trip regularly
• Fuses blow often (if you still have a fuse box)
• Lights flicker or dim
• Outlets don't work or work intermittently

Visible Wiring Issues

• Frayed or cracked wire insulation
• Exposed wires anywhere
• Burn marks on outlets or switches
• DIY wiring that looks questionable

Home Age and History

• Built before 1950 (may have knob-and-tube)
• Built 1965-1973 (may have aluminum wiring)
• No updates since construction
• Previous DIY additions

Insurance or Sale Issues

• Insurance company requires update
• Home inspector flagged wiring
• Can't get insurance with current wiring

Types of Old Wiring

Knob-and-Tube Wiring (Pre-1940s)

Individual wires run through porcelain tubes and around porcelain knobs. Characteristics:

• Wires separated by air space (no ground wire)
• No grounding
• Insulation may be brittle or missing
• Often inadequate for modern loads
• Can be covered by insulation (fire hazard)

Status: Not inherently dangerous if in good condition and not overloaded, but most insurance companies won't cover it.

Cloth-Covered Wiring (1920s-1960s)

Rubber-insulated wires with cloth covering. Issues:

• Insulation becomes brittle with age
• No ground wire in early versions
• May have degraded rubber exposing copper
• Often undersized for modern loads

Aluminum Wiring (1965-1973)

Used during copper shortage. Problems:

• Expands and contracts differently than copper
• Connections can loosen over time
• Creates fire hazard at outlets and switches
• Requires special handling

Status: Can be made safe with proper connections (COPALUM crimps or approved devices), but often better to rewire.

Full Rewire vs. Partial Update

When Partial Update Works

• Only one area has problems
• Adding circuits for specific needs
• Existing wiring is copper and in good condition
• Budget constraints (address worst areas first)

When Full Rewire Makes Sense

• Knob-and-tube throughout
• Widespread aluminum wiring
• Insurance requires it
• Major renovation planned anyway
• Multiple electrical issues
• Planning to sell

What Does Rewiring Involve?

A full house rewire typically includes:

1. Panel Upgrade

New 200-amp panel with modern breakers, proper grounding, and room for current and future circuits.

2. New Circuits

Run new wiring to all outlets, switches, and fixtures. Modern code requires:

• More outlets per room
• GFCI protection in wet areas
• AFCI protection in living spaces
• Dedicated circuits for major appliances

3. New Outlets and Switches

Replace two-prong outlets with grounded three-prong, add GFCI where required, install modern switches.

4. Proper Grounding

Install ground rods, bond electrical system properly.

5. Inspection and Permit

All rewiring requires permits and inspections.

The Process

Planning Phase

• Electrical assessment
• Design new system layout
• Determine access points
• Plan for minimal disruption

Installation (typically 3-5 days for average home)

• New panel installation
• Run wires through walls, attic, basement
• Install new outlets and switches
• Make connections

Restoration

• Patch any holes made for access
• May need some drywall repair
• Final cleanup

Inspection

• City or county electrical inspection
• Required before energizing new circuits

Minimizing Disruption

A skilled electrician minimizes wall damage by:

• Using attic and basement access where possible
• Fishing wires through existing paths
• Strategic hole placement
• Patching all access points

Older homes with plaster walls require extra care.

Cost Factors

Rewiring costs depend on:

• Home size (square footage)
• Number of floors
• Attic and basement accessibility
• Wall type (drywall vs. plaster)
• Existing wiring removal needed
• Permit requirements

We provide detailed quotes after assessment so you know exactly what to expect.

Insurance Considerations

Many insurance companies:

• Won't insure homes with knob-and-tube
• Require updates to aluminum wiring
• Offer better rates after rewiring

Rewiring can actually save money long-term through lower insurance premiums.

Service Areas

We rewire homes throughout the St. Louis metro including Chesterfield, Ballwin, Wildwood, Creve Coeur, Town and Country, Manchester, Kirkwood, Webster Groves, O'Fallon, St. Peters, St. Charles, Wentzville, Lake St. Louis, and Cottleville.

Get Your Home Assessed

Not sure if your home needs rewiring? Schedule an assessment and we'll evaluate your wiring, discuss options, and provide recommendations.