Aluminum Branch Wiring: the 1965–1973 problem, explained
1965–1973CommonInsurance flagElectrical
Quick answer
Homes built between 1965 and 1973 commonly used Aluminum Branch Wiring. CPSC-sponsored research found such homes far more likely — a widely cited 55 times — to have connections reach fire hazard conditions than copper-wired homes. Below: 3 identification steps for your inspector to run, the questions insurers ask, commonly cited repair costs, and links to the source documentation behind the year range.
Why it matters
CPSC-sponsored research found homes wired with pre-1972 aluminum branch wiring are far more likely — the widely cited figure is 55 times — to have connections reach fire hazard conditions than copper-wired homes. Aluminum expands, creeps and oxidizes at terminals, loosening connections over decades.
Era boundaries: Copper prices drove the switch in 1965; installs tapered off after 1972, but pre-1972 wire stock lingered in some builds through 1973–1974.
How to identify it
This is an inspector or licensed-trade task — the steps below are about recognizing clues safely, not opening equipment or sampling materials yourself.
- Look at exposed cable jackets in the attic, basement or garage for the marking AL, ALUM or ALUMINUM printed every few feet
- Check the era first: homes built or expanded 1965–1973 are the core window
- Do not open the electrical panel yourself or pull outlets — confirming conductor metal at terminations is an inspector/electrician task
Ask your inspector
- “Is the branch wiring aluminum, copper or mixed — and how was that verified?”
- “Have connections been remediated with COPALUM or AlumiConn connectors, and is there documentation?”
- “Should we price a per-connection remediation before closing?”
What fixes commonly cost
Connector-based remediation is commonly cited at $85–$200 per connection, and a typical house has 200–450 connections; full rewires are often quoted in the $8,000–$15,000+ range.
Ranges are commonly cited figures, not quotes — access, region and scope move real prices in both directions.
What insurers ask
A standard question on many homeowner applications and 4-point forms; carriers often accept documented COPALUM or AlumiConn remediation in lieu of a rewire.
Frequently asked questions
How do I know if my house has aluminum branch wiring?
Start with the era: Homes built between 1965 and 1973 commonly used Aluminum Branch Wiring. The fastest visual check: Look at exposed cable jackets in the attic, basement or garage for the marking AL, ALUM or ALUMINUM printed every few feet. Beyond that first look, verification belongs to a licensed inspector or trade professional — this is not a DIY check.
When was aluminum branch wiring used in homes?
Homes built between 1965 and 1973 commonly used Aluminum Branch Wiring. Copper prices drove the switch in 1965; installs tapered off after 1972, but pre-1972 wire stock lingered in some builds through 1973–1974. Boundary years deserve extra care: material stock and local practice never switched overnight, so a build within a couple of years of the range can go either way.
Do insurance companies care about aluminum branch wiring?
A standard question on many homeowner applications and 4-point forms; carriers often accept documented COPALUM or AlumiConn remediation in lieu of a rewire. Bring documentation: permits, remediation invoices and inspection reports answer the question faster than assurances.
How much does it cost to fix aluminum branch wiring?
Connector-based remediation is commonly cited at $85–$200 per connection, and a typical house has 200–450 connections; full rewires are often quoted in the $8,000–$15,000+ range. Get local quotes before closing when this item shows up — regional labor rates move these figures substantially.