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Inspection Spotlight: Electrical System Deficiencies
by Charles R. Rushmer, P.E., Chief Engineer
Let's talk about the electrical system in the house you are considering. Whenever I do an inspection, the deficiencies in the electrical system always get a lot of attention. Like all deficiencies, they can cost you money, but those in the electrical system can also "bite" you.
To begin with, let's make sure that we understand the difference between amps and volts. All dwellings are supplied with 120 volts, with a higher voltage of 240 volts. We used to call it 110 and 220 volts, but today it is closer to 120 and 240. The service panel (fuse box or circuit breaker panel) determines what maximum amperage you can get. The water analogy sometimes makes it easier to understand amps and volts. The voltage is like the water pressure. Higher voltage means the electrons are more energized, like "Arnold Schwarzenegger" electrons. The amperage is just a method of counting how many electrons come in to work. You hardly ever use all the amperage you are allowed, but the voltage is always the same.
Once you find the fuse box or circuit breaker panel, you should have easy access in front of the panel to inspect it or work on it. I have occasionally found a panel buried deep inside a closet with tons of stuff in front of it. If an emergency occurred, where someone might want to turn off the electricity quickly, they couldn't do it. It is important to have easy access to this important piece of equipment. The panel should not show a lot of corrosion. If it is a fuse panel, make sure there is an inside cover so that you can unscrew a fuse without the danger of touching a hot wire.
People assume that a circuit breaker is inherently safer than a fuse. Actually, in a corrosive environment, a circuit breaker could freeze in the "on" position and fail to "trip" when an emergency actually occurs. A fuse just has a frangible link that melts when too much current passes through it. The circuit breaker can be easily reset, but you have to go to the hardware store and buy a new fuse when it blows. There are problems with fuses, including the potential for putting a penny behind them. The biggest problem was that we made the 15, 20 and 30 amp fuses with the same screw base so that they were interchangeable. It took Uncle Elmer about three trips to the hardware store before he discovered that the green fuses didn't cost any more then the crummy blue fuses and they lasted a lot longer! Most old wiring was rated at 15 amps, and, therefore, needed a fuse rated at 15 amps. These fuses were almost always blue. The green fuses were almost always rated at 30 amps. Using a fuse (or breaker) that is too large allows the wire to overheat and possibly cause a fire.
There are only a few places where you can actually see the wiring in a house. If you climb up into the attic or crawl into the underfloor crawl space, the wiring is there for you to see. If you have a basement with an unfinished ceiling, the wiring can be visible as it passes through holes in the floor joists above you. The theory is that someday you will nail gypsum wallboard up on the ceiling and cover the wiring (and plumbing and heating ducts). If the wiring is stapled to the bottom edges of the floor joists, that's a code violation. It may seem like a small difference in location, but it turns it into a code violation. In the garage, if you have an unfinished wall, the wiring can be visible if it passes through holes in the studs. Again, it is assumed that someday you will nail gypsum wallboard up on the walls and hide the wiring.
The wiring used before the second world war was called "knob-and-tube" wiring. The hot and neutral wires were kept separate and protected with ceramic knobs and tubes. We had to keep them separate because the insulation in those days was not very good. We hadn't yet invented plastic, which makes a very good electrical insulator. In those early days, connections were made without junction boxes. The wires were coiled together and soldered and taped with friction tape. That is legal today only by the "grandfather" clause. If you see modern "Romex" wiring attached to knob-and-tube wiring without a box, it is not legal. People always ask if knob-and-tube wiring is safe. In my inspections, I have not found a lot of dead bodies lying around old knob-and-tube wiring, so it must not be terribly unsafe. Seriously, knob-and-tube is somewhat less safe than modern wiring. In the same way, grounded wiring is somewhat safer than ungrounded wiring. The difference in safety is not enough to warrant declaring that all old houses need to be rewired. There are a number of lending institutions that say they will not lend money on houses with knob-and-tube wiring, and there are insurance companies that say they will not insure houses with knob-and-tube wiring. If a house was originally wired with knob-and-tube wiring (any house built before the second world war), the chances are it still has some knob-and-tube wiring somewhere that is still active. When the kitchen is redone, it gets new wiring. The addition on the rear may have new wiring, but somewhere in the house there are lights or outlets still using knob-and-tube wiring. A house has to be "gutted" to replace all of the wiring, and this seldom happens. My experience is that something like 95% of houses built before the second world war still have some knob-and-tube wiring.
It would be nice to know if your "new" house has any aluminum wiring. Aluminum wiring caused some fires when it was first introduced. The aluminum industry had tried to get aluminum wiring used for a long time, but it was not used much until the Vietnam War. Every time you shoot someone, you waste the brass casing for the bullet. The major ingredient in brass is copper. We "wasted" a lot of copper in the Vietnam War and did not have enough for the housing market during that period. When the electrician went down to the supply store for the wiring for your new house, he was told they were out. He could use aluminum wire or take a vacation. It wasn't his house, so he used the aluminum wire. Aluminum wire can be made safe without completely replacing it, but this should be done by an electrical contractor. To see if you have any aluminum wire, you have the choice of taking off all the outlet and light switch cover plates, or removing the cover for the circuit breaker panel. I say circuit breaker panel, because by the Vietnam War, we had pretty well switched over from fuses to breakers.
All connections in the wiring must be inside a junction box of some type. The box can be metal or plastic, round or square, as long as it is a UL-approved box with a cover. If you see an electrical cable with a big gob of black tape at one spot, it is probably a connection. This can be dangerous and must be placed inside a junction box. This is one of the most common electrical deficiencies we find that is of importance. Many times, I have gone up into the attic and found electrical connections with no box where the homeowner has been adding a new light or ceiling fan.
Another thing we are always interested in determining is if "Joe Homeowner" has been doing his own electrical work. There are several things that would indicate this:
1. Sloppy wiring, or wiring that is visible in the living area
Whether an outlet is properly grounded or has the proper polarity can be determined with a simple polarity checker that can be purchased at any hardware store. Polarity refers to the fact that one of the slots in your outlets is short and one is long. The short one is supposed to be the hot wire, and the tall slot is supposed to be the neutral wire that has no voltage. The neutral wire is the return wire for the electrons after they have done their work. The "mouth" below the two "eyes" is supposed to be for the ground wire. It never has any voltage or amperage unless something has gone wrong. It is for emergencies only. Houses built before about 1963 did not have wiring with that extra ground wire, so in those houses, the outlets should have only two slots.
If you want extra safety, you can install the newer outlets with the two little push buttons. They are called GFCI outlets, which stands for "ground fault circuit interrupter." A regular fuse or circuit breaker breaks the circuit only if the flow of electrons exceeds the rating on the fuse or breaker. Sometimes, this is way too late. Before the invention of the GFCI, some kids were electrocuted in the bathtub. If an electrical appliance fell into the water, whether it was turned on or not, the kids were gone before the fuse could blow. The GFCI outlet does something different from a regular fuse or breaker. It measures the outgoing current and compares it to the return current. Remember, the enthused electrons come out of the black (hot wire) and go to the appliance to do some work, but the same number come back on the white wire after they are pooped. If all of the electrons don't come back, the GFCI trips in 1/60th of a second, and at less than one amp. This is fast enough to save your life. They were first required in about 1978 in bathroom, garage and exterior outlets. In 1990, the kitchen was added. To properly check one of these outlets, you should plug something into it and then press the button. About 20% of the time, they don't work properly.
There are other things that can be important about the electrical system, but this is a good start.
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