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Top 10 List of Hair Raising Wiring Problems

Why just about every homeowner, mechanic, handyman and engineer think they are capable of doing electrical work is beyond comprehension? As a home inspector, I find hazards and life threatening problems in the overwhelming majority of homes. That’s correct: majority!

Believe it or not, it’s not just as simple as connecting two wires. Some of the most common wiring problems found during a typical home inspection are listed below. Are they in your house? Before you review this list, understand that just because your “handyman” wiring works, does not mean that it’s wired properly or safely. The National Electrical Code (NEC) is the code that all electricians operate under. There may be some local interpretations around the country, but for all intents and purposes it is the minimum standard for safety. If your wiring does not comply with the standards, one day you could have a fire or get electrocuted. It happens. How often do we hear about house fires that start for “no apparent reason”?

The National Fire Protection Association (NFPA) says electrical problems are the largest cause of property damage in home structure fires. Add to that, the United States Consumer Product Safety Commission (CPSC) states small appliances plugged into inadequate and improper house wiring is the leading cause of accidental electrocutions.
To be more specific, NFPA statistics for 2002 reported 389,000 reported home fires in the United States home that resulted in 2,670 deaths, 13,650 injuries and 5.9 billion dollars in direct property damage. What follows are the most common wiring problems found during a typical home inspection. They are not in any particular order of signature or frequency, just very common and hazardous.

1. Grounded receptacle improperly wired
Ungrounded receptacles are converted to accept newer 3-prong plugs without connecting the ground wire. The illusion is that the receptacle is grounded but in reality, it is not. Properly grounded outlets allow stray current (yes stray current) to travel to the ground and not into you, if a malfunction occurs.

Another problem commonly found on inspections is receptacles wired improperly with the hot and neutral wires reversed. All electrical devices today are polarized. That means the small slot in a receptacle should be hot and the larger slot is neutral. The half round opening is for the ground wire. If improperly wired, (i.e. reversed polarity), there is an opportunity for electrical shocks.

2. Frayed service entrance conductor
The utility company is responsible for the power and equipment up to the point the overhead or underground wiring touches your house. After that, it’s your responsibility. Many people never inspect the service line coming down the side of their house. It can become loose, cracked and frayed. Bare wires become exposed. This can eventually lead to shorts and a fire. According to Mike Brennan of Brennan Electric in Troy, Michigan, this allows water to get into your service box and if memory serves me properly, water and electricity are not compatible.

3. “Homeowner” wiring
Whether done by the homeowner or the handyman they hired, homeowner wiring is always a problem. Inspectors find loose, hanging wiring and open junction boxes. We find wiring under joists or connections not in boxes, inadequately sized wiring and/or switches (which means not heavy enough to handle the load). We also frequently find improperly wired switches, fixtures and service. This category is probably responsible for the majority of lost lives and fires. Any wiring done by a homeowner or handyman and not done by a licensed electrician should at least be inspected by one.

4. Inadequate service for today’s requirements
Most houses are built with minimum electrical service. That’s always been true. Nowadays with 1500-watt hair dryers, microwaves, frost-free refrigerators, and computers along with all the other conveniences we want, our electrical service may be inadequate. That is especially true if your house is over 40 years old. Do your lights dim when the air conditioning or fridge turn on? Do you blow fuses or trip circuit breakers frequently? If so, consider upgrading your service.

5. Extension cord wiring
Many people use extension cords all the time. They should never be considered permanent wiring. Extension cords should never be installed under rugs or covered. Excess cord should not be bundled or rolled up because it could cause overheating. They should periodically be inspected to make sure they are not warm, overheating, brittle or cracked. Extension cords have “gauges” or sizes. The proper gauge and length should be used with the load required. Undersized cords, 16-gauge or smaller, can overheat and cause a fire. Never use “octopus plugs” or numerous cords plugged into a single receptacle. The main reason people rely on extension cords is because they do not have enough wall outlets. Today’s codes require a receptacle on every wall over 4-feet in length, as well as within 4-feet of a doorway. There should also be one on every wall that can be reached by a standard 6-foot cord.

6. Oversized fuses or breakers
I don’t think there is a day where I don’t find oversized fuses or even circuit breakers. The fuse or breaker is supposed to be the weakest link in the circuit. If there is a “situation” you want the fuse to blow or the breaker to trip. By increasing the size, the homeowner has not increased the power to that circuit. They have made the wiring within the walls the weakest link and that could cause a fire. The house could burn to the ground and hypothetically, the only thing left standing will be that oversized fuse or breaker. Installing oversized breakers is a problem inspectors find that even licensed electricians occasionally make. Whether it is because they don’t want to go back out to the truck, or don’t have the proper size breaker, it still is a potential fire hazard.

According to Brennan you should never use any 30-amp fuses and only use 20-amp fuses for kitchen and laundry circuits.

7. Aluminum wiring
Houses built between 1960 and 1973 could have some aluminum wiring. There was a copper shortage because copper was used for shell casings in ammunition due to the Vietnam War (it was in the papers). So, an inexpensive substitute was aluminum, but what no one considered was that aluminum wiring expands and contracts at a different rate than the copper and brass screws used on all fixtures and outlets throughout the house. Aluminum also corrodes when it is in contact with copper. Thus numerous fires occurred and aluminum wiring was discontinued. Nevertheless tens of thousands of homes have aluminum wiring within their walls. It can be replaced, but it is expensive.

Recent technology called Arc-Fault Circuit Interrupters (AFCI’s) can be installed in place of existing breakers. The AFCI will immediately sense overheating and/or arcing, and shut off the current to the circuit.

Brennan says an electrician can install AL/CU wire nuts with copper tailpieces onto aluminum wiring connections throughout the house, which could reduce the chance for a fire.

8. Knob and tube wiring
Many older homes have knob and tube (K&T) wiring which is the earliest type of residential wiring. K&T looked like individual cloth covered wires approximately 8 to 12 inches apart. The wires were secured with white ceramic knobs and tubes. Much of it is still in use today but problems arise when connections are taken off the wiring. The wiring can also become brittle and the solder joints can weaken. Any one of the above are problematic and hazardous, but as long as it is in good condition, K&T wiring can last for many more years. If you have this type of wiring and are planning any major remodeling, at that time you should consider updating the service and replacing the wiring.

9. No Ground Fault Circuit Interrupter (GFCI’s)
GFCI’s sense a fault to ground (read that as being electrocuted) and cut off the power within 1/4oth of a second. That means it’s off within 3 to 5 milliamps, which is before the average person would be seriously injured. They are required in all new construction for exterior, garage, basement, bathroom and kitchen circuits. They can and should be retrofitted into all existing homes. In addition, AFCI’s, which were discussed previously, should also be installed in all existing homes.

10. Worn out receptacles
Yes, wall outlets wear out. If you plug a cord into an outlet and it falls out or is loose, it means the receptacle has worn out and the contacts can arc, causing fires. This is another area where AFCI’s can prevent a fire, but the receptacle should be replaced.

This article contributed by:

Lon Grossman 
Technihouse Inspections Inc.
4940 Rands Road
Bloomfield Hills, MI  48302

Contact Lon today to schedule an inspection!