If you have had a home inspection in the past say, 300 years, there is a good chance your inspector wrote something in the electrical section of your report along these lines:
“One (or more) double tapped breakers noted in the electric panel. The inspector recommends further evaluation and proper repair by a licensed electrician.”
A comment in your home inspection report like this one is horrible. Besides being one of the worst written explanations of a problem I’ve ever forced my fingers to type, it leaves you, the buyer/homeowner with little to no information about what the heck is going on here.
Unfortunately, most home inspectors do not take the time to actually write proper explanations about the problems they discover during an inspection, and poorly written comments like the one above leave the Realtor and buyer scratching their heads about what needs to happen. My goal with this article is to explain what a ‘double-tap’ is, and how it can be corrected.
What is a Double Tapped Breaker?
A double tapped breaker, more commonly know as a ‘double-tap,’ is when more than one wire is connected to a breaker (or to a busbar-but we are only going to talk about breakers for this post) in an electric panel. The curveball here is that some breakers are designed to accept multiple wires and it’s not a problem with those types.
Circuit breakers are designed to protect the circuit, not what is connected to them. In other words, we want to make sure the wires stay in good working order and don’t melt down to start a fire. Let’s first look at how to determine how many wires a breaker will accept, and then we’ll look into how to fix the problem if you have too many connections on a breaker. This, of course, is known as a double tap, or even a triple tap if you have an extra stupid person working inside your electric panel.
Why are double tapped breakers a problem?
It’s all about the connection between the wire and the breaker. If more than one wire is connected to the breaker, and that breaker is not designed for two wires, the chances of those connections being too loose is much greater than those with just one wire connected.
If the connection between a breaker and a wire becomes loose, it could cause overheating or worse, start to arc between the gaps. Arcing is what starts a fire in an electrical panel. Making sure your breakers’ connections are tight and properly executed is very important to fire safety.
Note: The issue with double tapping a breaker has nothing to do with the load (demand) on the circuit. I see a lot of bad info floating around saying that more than one connection on the breakers can cause an overload. That is 100% false.
Some Double Tapped Breakers Are Not A Problem
As if the rules aren’t confusing enough, sometimes you can double tap breakers and it’s not a problem. There are a couple manufacturers that rate and allow certain breakers to have these types of connections made to them.
So how do you know which is which? It’s printed on the breaker.
As far as I know, these Square D’s and some Cutler Hammer breakers are OK to double tap, but everything else is a no-no. If you know of another brand where this practice is acceptable, please let me know and I’ll add it to the list.
Note: Notice that both of these breakers state that you should not double tap the connections if aluminum wire is involved. When aluminum (AL) wire is present, it is stated that you are only allowed a single connection. Homes with aluminum wire have a whole different set of rules that you can learn more about here.
How to repair a Double Tapped Breaker
Now that you know you how to determine what a double tapped breaker is, let’s explore the options on how to correct them. These are all fairly simple, but if you don’t have past experience or knowledge with working inside an electric panel, it would be best to call in a pro. There are points inside these panels that can kill you in the blink of an eye, even if you turn off the main breaker.
If all else fails
The vast majority of the time, one of the options above will take care of your double-tapped breaker woes. If you find yourself in a situation where it won’t, sometimes a larger panelboard may needed- but those times are few and far between. Only your electrician can tell you for sure when it comes needing a replacement panel.
For all the young and budding home inspectors out there who happen to read this, please feel free to steal my wording that I use for my home inspection reports about double tapped breakers. Don’t be that guy who writes crap like I have at the top of this post and call it an “explanation.” Be detailed. Be descriptive.
“The panelboard has (insert number of double taps) double tapped breakers located (insert location of said breakers). Double tapped breakers are an unsafe condition in which multiple conductors are placed under the set screw of a single breaker. When multiple wires are connected to a breaker, you greatly increase the risk of a loose connection, which can lead to overheating, arcing, and electrical fires. It’s typically a fairly simple repair so be sure to have an electrician evaluate the situation and correct things as needed.”
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