Old Homes and Bad Electrical Connections

The housing stock in the San Francisco Bay Area is quite varied. Our jobs have been located in houses ranging from turn-of-the-century Victorians to modern townhouses or condominiums. This difference in ages will undoubtedly lead to an assortment of previous construction practices that we see.

A majority of our business is to upgrade old homes to modern standards. When we open up walls, we are able to see how the last builders did things. A particular area that has come to our attention is the electrical systems in late 1950s and early 1960s homes. A common practice of connecting wires then has been shown to possibly cause problems further down the road.

Residential electricity is AC or “alternating current”. This means that the electricity will go on and off about 60 times a second. Back in the time period mentioned, a wire connection was either simply “crimped” (pressed together with a wire inside) or the wires were first twisted before being crimped inside the connection. Both ways used electrical tape to finish the job. The problem with only a crimp is that, because of the alternating current, the wire will expand and contract over time. This can loosen the connection, and if done enough, the wire can heat up and possibly “arc”. An “arc” is where electricity jumps across any space, in this instance, within a connection.

This situation can lead to power loss at the least and a fire hazard at the most. We have seen extreme examples where an area within the wall was burned. This is by no means a normal occurrence, but being mindful of the possibility is important. New electrical connections are done by tightening a nut, ensuring a strong fit and bypassing this problem.

A few things to look out for:
• Warm wall outlet, switch or light outlet. Dimmer switches are meant to run warm and are of no concern
• Flickering lights
• Appliance motors running slow
• Coffee makers or toasters not heating quickly
• Burning smell of plastic or wood

Places to look for a problem:
• The first light outlet closest to the meter/main (where power comes to the house from the street) or sub-panel (where breakers are inside home).
• When using an aftermarket wall heater, check outlet closest to meter/main or sub-panel.
• In the sub panel, check for warm or hot circuit breakers by touching them on the front side.

This information and first-hand knowledge was provided to us by Alan Woertink of Woertink Electric. His contact information is at the top of this blog. Feel free to contact him regarding any electrical concerns or repairs. Please call us regarding any other “old house” issues you may have. We have been repairing and upgrading homes since 1994.