Typically, breakers are not designed for more than one copper wire connected to them. Double-tapping occurs when two electrical wires are connected to a breaker rated for only one wire connection. Double tapped breakers can overheat, and wire connections can become loose, causing the breaker to arc or trip frequently. In some cases, a house fire can occur.
A double-tapped breaker, ‘double-tap,’ occurs when two circuit wires are connected to a single-pole breaker. You can fix double-tapped breakers by installing a pigtail wire connection, adding a circuit breaker, a tandem breaker, or a breaker with a 2-pole rating. A double-tapped breaker costs about $150-$250 to fix.
Double-taps are a common defect in an inspection report, but it is easy to correct. In this article, we will look at why double-tapped breakers are dangerous. Moreover, we will also tell you how to fix a double-tapped breaker to ensure your safety.
What is a Double-Tapped Circuit Breaker?
A double-tapped breaker is an electrical hazard where two or more wires are connected to a single breaker rated to receive one wire connection. Breakers come in two types, “1 pole” or “1 or 2 poles”. Breakers labeled “1 or 2 poles” are rated to receive two circuits, while a “1 pole” breaker is only rated for one circuit.
Double tapped breakers are dangerous because the breaker can overheat and trip frequently. Two electrical wires connected to a single rated breaker reduce the resistance, causing the breaker to overheat, trip, or fail suddenly. The wire expands and contracts as the circuit overheats, creating loose connections that can arc and cause a house fire.
Are Double-Tapped Breakers Allowed?
When people ask if a double tapped breaker is illegal, we assume they refer to electrical codes. Double tapped breakers are against national electrical codes and manufacturer guidelines unless the circuit breaker is rated explicitly for two poles.
Electrical updates have to follow NEC codes at the time of the change. When unwritten, the electrical code follows manufacturer specifications.
There is no direct mention of the National Electrical Code (NEC) regarding double tapped breakers and whether or not they are allowed. However, manufacturers rate their breakers for one or two pole connections.
Circuit breakers are clearly labeled to receive a single or double-wired connection. At 110.3(B), the NEC statement states that equipment labeling should only be installed and used as the instructions list. Therefore, because the manufacturer specifies how the breaker should be connected, we can derive that double tapped breakers are not allowed.
Why Would Someone Double-Tap a Breaker?
Double tapping a breaker can be done when the electric panel box does not have adequate space to connect all the wiring circuits. Often, a homeowner or amateur electrician looking to get the job done quickly might double-tap the breaker to avoid the hassle of either replacing the electric panel entirely or purchasing a breaker designed for two circuit connections.
The best way to know whether or not the double tapping of the breakers on your house’s electrical panel is a defect and potentially dangerous or not is to read the label of the breaker that has been double-tapped. If a breaker allows for two circuits, it will clearly state so on the breaker.
How to Fix Double-Tapped Breakers
The good thing about double tapped breakers is that they can be relatively easy and cheap to fix. There is more than one way to fix double tapped breakers, which means you can choose whichever method is the most comfortable and convenient for you. First, you’ll need to remove the panel cover to access the breakers.
Install a Pigtail Repair
The quickest and cheapest repair for a double tapped breaker is to create a pigtail connection inside the electrical panel. A pigtail connection is a simple repair by connecting the two wires to a third extra wire from the breaker. Use a wire nut to secure the three wires together. Finally, insert the third extra wire into the breaker and tighten. There is now one single conductor connected to a single circuit breaker.
The pigtail connection repair option will only work provided the circuit breaker is not overloaded. The breaker should not exceed 80% load of the breaker rating or carry 100% of any non-continuous load plus 125% of any continuous load. Some ways to tell if the circuit is overloaded is if the breaker is overheating or tripping routinely. If you have questions, consult a licensed electrician.
Add a New Circuit Breaker
If an open breaker slot exists, the safest and best repair is adding a breaker into the box to have two separate circuit breakers. However, this may not always be an option. Double-tapped breakers often occur because the electric panel is at full capacity with no single circuit breaker slots available.
Install a Tandem Circuit Breaker
A tandem breaker is a double breaker that fits into a single breaker slot in the electrical panel. Tandem breakers have two “1 pole” connections with individual trip handles.
Installing a tandem circuit breaker is an excellent alternative if the electrical panel manufacturer allows it. This option may not be suitable for older electrical panels.
A tandem breaker costs about $25-$40 per breaker plus labor for the installation. Installing a tandem breaker will take about an hour to complete. The panel data plate should tell if you can install a tandem breaker. If you’re not sure, contact a qualified electrician.
Install a Two-Wire “1 or 2 Pole” Rated Breaker
A two-wire “1 or 2 Pole” breaker is a single breaker with two slots to connect two wires safely. You can quickly identify a two-wire breaker because “1 or 2 Pole” will be printed on the breaker tag or stamped on the front of the breaker.
Like tandem breakers, installing a two-wire circuit breaker is an excellent alternative if the electrical panel manufacturer allows it. This option may not be suitable for older electrical panels.
A two-wire breaker costs about $25-$40 per breaker plus labor for the installation. Installing a two-wire breaker can take about an hour to complete. The panel cover diagram will tell if you can install a two-wire breaker. If you’re unsure, consult a qualified electrician.
Lastly, if your panel is:
- overloaded with all double-tapped circuits
- is at maximum capacity with no available breaker slots
- the service panel manufacturer does not allow for tandem or two-wire breakers
An electric panel upgrade can be significantly more expensive and longer to repair. The national average cost to replace an electrical panel is about $1500 and can be as high as $4000.
Installing a subpanel to move some circuits into can cost $500 to $1500. The cost of installing a subpanel will vary based on the subpanel location, the amount of electrical wiring needed, and the number of added circuits.