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Can
Your Home Wiring Handle the Load?
Home theaters, home
offices, whirlpool tubs, video games, rechargeable tools, appliances and
personal computers—the landscape of our lives has changed dramatically in
the past few years, reshaped by new and ever more sophisticated electrical
products. But our need for increased power to operate these devices has,
in many cases, outpaced our homes' ability to serve and protect
us.
It's hard to believe that, not long ago, the standard
electrical service installed in most homes was only 60 amps (for
comparison, consider that many central air conditioning systems alone can
draw up to 40 amps, and electric ranges often need 50 amps). But 60-amp
service was once considered sufficient power for all of the plug-in
appliances and permanently wired fixtures a typical home possessed. Of
course, those were also the days before televisions in every bedroom,
multiple-computer households, and the proliferation of electric appliances
for teenagers to use on their hair.
Today the required minimum for
new homes is 100-amp service, according to the current edition of the
National Electrical Code. But even this modern "standard" may fall far
short of adequate for many families—now, and in the not-too-distant
future. "If you're a smart homeowner, you want to go well above the
minimums. You want to add more circuits and more capacity," advises David
Brender of the Copper Development Association. A member of one of the
NEC's Code-making advisory panels, Brender along with other industry
experts, helps to review and propose changes that keep the electrical code
up to date with improvements in technology and changing
lifestyles.

The graph above shows
the annual sales of electricity, in billions of kilowatt-hours, to U.S.
homes over the past five decades. The trend illustrated shows why most
homes built before 1989 are poorly equipped with electric service for
today's demands.
Brender is quick to point out that
like all construction and safety codes, the NEC sets baseline
standards only. Homeowners can, and often should, exceed the
Code recommendations when they build, repair or renovate.
For example, anyone expanding the electrical capacity in their
home would be wise to consider installing a higher-capacity
panel—150 or 200 amps—if they have a growing family, or expect
further home expansions in the years ahead.
Another smart move is to use 12-AWG copper wiring as a minimum
size for all new electrical installations, even for those
circuits protected by 15-amp breakers. Although thinner 14-AWG
wire is allowed for most residential applications, the heavier
12-AWG wire runs cooler and is more energy-efficient. You'll
also benefit right away from the extra margin of safety it
provides, and you won't have to run new wiring a second time
if the circuit needs to carry more current in the future.
(You can simply change-out the breaker from 15 amps to 20
amps.)
According to Brender, even professionals must be encouraged
to think ahead when called in to perform routine electrical
work. The Code presently allows electricians to calculate
a home's power needs (in total watts) by multiplying the living
space, or square-foot area, by a factor of three. In Brender's
view, increasing that factor by at least 50 percent
provides a more realistic margin for anticipated energy use
in the years ahead. A recommendation to write this increase
into the electrical code has been proposed, but is probably
years away from adoption Homeowners who want to upgrade now
don't have to wait that long. [top]
Ground Rules for Household WiringIs your home
Code-compliant—and safe?
When it comes to
upgrading or repairing household wiring and electrical systems,
homeowners usually call a licensed professional to do the work. But
whether you own your home or rent an apartment, bringing the wiring
in your residence up to the current National Electrical Code could
enhance your safety—every time you flip a switch or plug into an
outlet.
The NEC sets the minimum electrical standards for
essentially all cities, states and municipalities throughout the
United States. In all likelihood, your local electrical codes are
based on rules set down in the NEC which is reviewed, revised and
updated every three years. Here are some Code highlights that should
concern you the most:
- Most homeowners are aware that the electrical system must be
grounded to the main incoming water pipe—right? But how many know
that that alone is no longer sufficient, according to the NEC?
Because increasing use of plastic water pipe and non-conducting
fittings has made the effectiveness of grounding to plumbing
systems questionable, the method does not meet current safety
standards. Although water lines still must be used in most
circumstances, the Code now states that the home may also require
one or more "supplemental grounding electrodes" buried in the
house foundation or in the earth outside the home. One or more
copper-clad grounding rods several feet in length are often
recommended. Local code-enforcement may also require that
grounding rods be added to existing homes when new electrical work
is done, or if you sell your home.
Ground-fault circuit interrupters,
which most codes require for electrical outlets installed in
kitchens, baths, laundry rooms and garages, automatically shut off
power to the circuit on which they're installed when their built-in
sensors detect a shock hazard.
- To increase safety in areas of the home where it counts the
most, the NEC requires that ground-fault circuit interrupters, or
GFCls, be installed in specific locations. Outlets in so-called
"wet" locations such as kitchens, baths and crawl spaces, as well
as in damp areas like unfinished basements, garages and outdoors,
now require GFCI protection. This can be achieved installing new
outlets with built-in GFCIs (identifiable by their "Test" and
"Reset" buttons), or by GFCI circuit breakers wired into the house
service panel.
- The latest innovation beyond GFCls are arc-fault
circuit interrupters, and beginning in January 2002,
these protective wiring devices will be Code-required
in circuits serving bedrooms. Arc faults occur when
thin electrical wires crimp and fray, which is typically
caused by crushing, bending and repeated impact.
Why bedrooms? Surveys show that bedrooms are most
likely to have exposed lamp cords and electrical
devices connected with extension cords—the type
of wiring most vulnerable to damage, which in turn
leads to arc faults. [top]
Smart Electrical Upgrades for Home
Remodelers
If your home
needs a makeover, or you're simply planning to upgrade your
decor, appliances or any other aspect of your living quarters,
now is the best time to consider upgrading your home
electrical system, as well.
Home repair and remodeling
projects often require some electrical work. As long as the
electrician is on hand, you can usually save the cost of a
service call by adding to the job as needed If you haven't
planned electrical upgrades, a quick look around your house
might convince you that you should. Do you have receptacle
outlets overburdened by multi-plug strips? Are your lamps and
fixtures connected to extension cords? Does every three-prong
plug need a two-prong adapter? These and other warning signs
indicate a real need for electrical
improvements.
Unfortunately, many homeowners wait until
a problem occurs, and only then do they think to call in an
electrician. But there's along list of reasons why you should
inspect and improve your electrical system—before an accident
or service breakdown occurs. Here are a few points to
consider, according to the Copper Development
Association:
- Is your service adequate? Many
older homes still operate with seriously
outdated 60-amp electrical service—and sometimes
with just a few fuses or circuit breakers
to protect the entire system. Newer homes
often have 100-amp service panels, but even
this minimum requirement set by many current
codes may fall short of your present or
future needs. Consider upgrading service
to 200 amps.
- Size for extra demand. If you're
installing a major electrical appliance,
like an electric wall oven, a microwave
oven, a double-wide refrigerator or central
air-conditioning, you'd better think about
the additional power it may need. While
a salesman or installer might tell you that
your system can handle the load, be smart
and ask your electrician for a second opinion.
- What's the correct wire size? Electricians
often install 14-AWG wiring during renovations,
which is adequate for most home uses. But
heavier 12-AWG copper wire is a better choice
because it's more energy-efficient and you
won't have to upgrade all over again if
you install appliances or fixtures with
greater electrical loads. The cost difference
for upgrading to 12-AWG copper wire is minimal.
If you're adding a room extension or building
a new home, it's a good idea to install
12-AWG wire (or larger, depending on the
needs of each circuit).
- Consider special needs. Different
rooms in a home serve different purposes—an
important consideration when you're planning
improvements, especially where electrical
work is involved. Family rooms, home offices
and home theaters generally need more circuits,
more outlets, and built-in or plug-in power-surge
protection. Outlets in kitchens, baths,
garages and outdoor areas require ground-fault
circuit interrupters, or GFCIs. And you
don't have to wait for a major renovation
to add protection—you can install many safety
devices yourself, such as outlet caps, switch
guards and wire shields in nurseries and
children's playrooms.
- And finally, don't forget your communications
wiring needs—make sure telephone wiring
is rated Category 5 or better to assure
speedy data mission, high-quality voice
service and convenient installation as you
add telephone-based services in the future.
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