Address Older Home Wiring

Not all homes were built yesterday. Or even a week ago, or even 20 years ago. Chances are that at some point you will be asked to rewire an older home.

Then you might encounter patchwork electrical systems—some installed by previous contractors, some not.

Of course, there are things you need to know about older housing and electrical equipment when you accept the job—and most of it comes down to knowing the electrical code of the house where you will be working, according to Keith Lofland, Education, Codes and Standards coordinator for the International Association of Electrical Inspectors (IAEI).

The first thing you need to do, he says, is to contact your local building inspection department; he even recommends this for the homeowner. “A lot of times, the local jurisdiction and the inspector get overlooked at the beginning of the job,” Lofland says.

Although inspectors must approve the home or project once completed, the reason for calling them in early is for you to understand the codes the house was built under. “You always want to find out when the house was built and what codes is was built to,” Lofland says. Although he speaks from an inspector’s point of view, he says it makes good sense to know all the codes you must abide by before starting work.

For instance, he says that if a house was built in 1970, then it is not required to have ground fault circuit interrupters (GFCI), which all homes now have, especially in bathrooms, bedrooms and kitchens. “What I have to do and what I choose to do are totally separate matters,” he says, adding that the decision to replace or repair electrical receptacles falls on the contractor. In fact, several codes are not retroactive, unless you are replacing receptacles in certain rooms—then GFCIs are required.

In addition to the codes you must adhere to, Lofland says you need to know what type of wiring you are working with: copper, copper-clad aluminum or aluminum, for instance. And depending on which already is in the house, then you need to adapt to them and use the proper testing equipment.

With all the talk of coming in contact with an older home’s wiring, if you are working within an addition to the home, then you must abide by the modern codes that are set forth by the jurisdiction where you are working, Lofland says.

“If you’re building a bedroom addition on the back of your house, then it has to be to the current code,” Lofland adds. “It’s new construction.”

So, what does Lofland look for when he inspects older homes’ wiring? He looks for what he is called there to look for, he says. He will know the code—and what exactly is required—going into the home. If it’s that same house built in 1970, then it won’t require GFCIs, and he won’t look for them specifically, except in cases of new construction. That said, if an electrical receptacle was replaced, it must be GFCI-protected; this is about the closest electrical code requirement that is considered to be “retroactive,” Lofland says.

A few other key points he looks for, and suggests addressing, are:

• potential fire hazards—and if fire alarms are present (these, too, have not always been required)
• the wiring method used in the home
• grounded vs. ungrounded receptacles (again, these have not always been necessary, depending on the code)
• electrical service to the home

The last point he mentions can be key because of all the new gadgets and appliances, regardless if it’s ENERGY STAR-rated or not, that have found a place in the home. Lofland says you should make sure that the electrical service provides enough capacity to accommodate the number of electronics and other equipment that homeowners can’t seem to live without.

If not, you may want to consider upgrading the panelboard, in which case you might consider installing GFCIs and arc fault circuit interrupters (AFCI), Lofland says.

But, as Lofland urges, “it all depends on what jurisdiction you’re in and what code is adopted.” Because not all municipalities are alike and they don’t adopt the same codes.