Electricity!
How Times Have Changed
Dishwashers, garbage disposals, microwave ovens, blenders, food processors, electric tooth brushes, electric blankets, CD players, DVDs, electric dryers, televisions, air conditioning, electric drills, electric screw drivers, and computers: common appliances of today, but unheard of 75 years ago. If your house was built before 1940, your life could be seriously curtailed by lack of electrical power. Oh, dear!
Prior to 1940, most homes only needed enough electricity to light the house and operate a radio and maybe a refrigerator. As a result, pre-1940 homes were equipped with 15 or 30 amperes and new homes with 40- and 60-ampere service. By the 1950s, most new homes had today’s standard 150-200 ampere service. Amperes represent the amount of electricity flowing.
You can go to the bother of calculating how much electrical service you need. You multiply amps (load) times volts (pressure) to get watts for everything in your house. Then, you add all the watts up. A watt is the amount of power available in a circuit. The National Electrical Code Handbook details several methods of doing this. Or, a much easier method is to assume you need or will soon need 200 ampere service.
Safety is the key. Unfortunately, electrical wiring doesn’t last forever. So if there is any question about safety or the condition of wiring, replacement or new service could be the most prudent thing to do. Electricity and its installation have changed dramatically during the past 100 years or so. Few homes prior to 1900 contained electrical systems.
The language of electricity is rich, and that’s what you may feel you have to be to replace it. Depending on the age of the home, some common terms include: “tree” type wiring, wooden cleats, knob-and-tube wiring, wood molding for wires, plaster concealed wires, conduit wiring and armored cable. Often, you will hear the word “fishing.” No, not fishing for Rainbow Trout. “Fish” is a special electrical tool used for rewiring. Fishing around a corner or a cornice is a real art.
Like people and animals, old wiring deteriorates. Some common problems include: deteriorated insulation, brittle metal, corrosion, and loosened connections. Fire can result. However, old wiring is often very serviceable and safe today. An electrician with experience working on old houses is very beneficial.
Adding more amps, called “new service,” if fairly easy, but expensive. Rewiring a house is expensive and tough. In either case, new codes are applicable and often involve many more electrical outlets than many owners of older homes find aesthetically pleasing.
The Old House Journal Guide to Restoration is an excellent educational resource. Visit oldhouseonline.com/10-tips-for-rewiring-an-old-house.
The old adage, “it’s better to be safe, than sorry,” certainly applies to electrical systems in old houses!
Elizabeth can be reached at historicgenie.com.