WHAT IS DOUBLE Lugging (ELECTRICAL)

By
Home Inspector with Bay Area Home Inspection, LLC WI 739-106

As a home inspector, I come across a variety of issues regarding electrical wiring. One of the most common safety defects I see is double Lugged breakers. I thought I'd just take a minute to explain what this issue is, and why a home inspector will call it out as a safety concern.

double tapping of breakers The 3 breakers on the upper right side all have 2 black wires entering in the back and held by a single flat screw. This is wrong for a couple reasons. First, it's against the NEC (electrical code).  "NEC 110.14(A) Terminals: .... Terminals for more than one conductor and terminals used to connect aluminum shall be so identified." In other words, if the breaker is not approved and labeled for 2 conductors (black wires), it is not allowed. 

I am aware of only one panel brand (Square D) that makes some breakers that allow 2 conductors. It's designed for that application as it has a special washer that accomodates these 2 wires. See below.

double tapping electrical

So, why is it a safety concern if not approved? Mainly, the issue is that the screw holds the wire securely to a conductor connected to the bus bar. If there are more than one wire being held by a flat screw, one could more easily become loose and start arcing. This is especially true when 2 different size wires are present such as 14 gauge and 12 gauge.

I most often see this issue when the panel is full and there are no more places to add breakers. The solution often is to pigtail these breakers or in some cases add a sub panel. In other cases, it makes sense to upgrade to a larger panel depending on what else might be going on inside the home.

Home this helps.

 

Comments (16)

Lynda White
Bluegrass Homes & Farms Realty, Agent Know How - Louisville, KY
Admin. Mgr., Keller Williams Realty

I didn't know this. Thank you for the education. I'm wanting to learn more about heating & cooling/electrical because my day job is a dispatcher for a company that provides those services. 

Apr 10, 2017 06:17 AM
Barbara Todaro
RE/MAX Executive Realty - Retired - Franklin, MA
Previously Affiliated with The Todaro Team

Good morning, Walt Fish that's a problem that surfaces with many home inspections and now we have a clear explanation of the issue...

Apr 10, 2017 06:18 AM
Kristin Johnston - REALTOR®
RE/MAX Realty Center - Waukesha, WI
Giving Back With Each Home Sold!

This comes up pretty frequently on home inspections here...great info!

Apr 10, 2017 06:33 AM
Pamela Cendejas
Second Self Virtual Assistance - Kingman, AZ
Second Self Virtual Assistance (928) 692-3235

I don't know anything about electrical but this looks scary even to me.

Apr 14, 2017 11:04 AM
Kathy Streib
Room Service Home Staging - Delray Beach, FL
Home Stager - Palm Beach County,FL -561-914-6224

Walt- it all looks hard for anyone but an electrician or inspector to figure out!  

Apr 15, 2017 01:33 PM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

It's just part of the job. Thanks!

Apr 15, 2017 02:14 PM
Lynn B. Friedman CRS Atlanta, GA 404-939-2727
Atlanta Homes ODAT Realty - Love our Great City - Love our Clients! Buckhead - Midtown - Westside - Atlanta, GA
Concierge Service for Our Atlanta Sellers & Buyers

Walt Fish 
Great and clear explanation! It is important that agents understand what shortcuts Sellers have taken. When I see this --- I am sure I will find other places where they have "bent" the safety rules. 
All the best- Lynn

May 21, 2017 11:54 PM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

Yes, it's an indicator for me as well Lynn.

May 22, 2017 12:19 PM
Brenda Whitman, Live in Laramie Real Estate
Live in Laramie Real Estate, Laramie, Wyoming - Laramie, WY
Broker/Co-Owner, Laramie, Wyoming

Very informative!  I've had inspectors call this out in inspection reports before and always wondered what exactly this was.  The photo helps a bunch!

Oct 13, 2017 07:41 PM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

Thanks Brenda. Its a common safety issue.

 

Oct 14, 2017 04:41 AM
Barbara Altieri
Better Homes and Gardens RE Shore and Country Properties - Shelton, CT
REALTOR-Fairfield County CT Homes/Condos For Sale

Have seen this a LOT, Walt, on inspections. Your explanation is excellent.  I learned it as double 'tapping'. 

Nov 12, 2017 06:39 PM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

Thanks for the response Barbara. Yes, I used that term for almost 20 years. Then a local electrical inspector supervisor for Marquette county pointed out that doble tapping (in the strictest sense) only refers to the main, not the branch wiring. The other hundreds of electricians I'd been in conctact with over the years understood immediately what I meant, but this guy did not. So I updated my description.   

Nov 13, 2017 05:09 AM
Silvia Dukes PA, Broker Associate, CRS, CIPS, SRES
Tropic Shores Realty - Ich spreche Deutsch! - Spring Hill, FL
Florida Waterfront and Country Club Living

Walt, this is a good explanation to a common issue that comes up in home inspections. In our area, it's known as double tap. 

Jan 09, 2018 05:49 AM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

I agree with you Silvia. That's the termonology most electricians use. 

Jan 09, 2018 06:50 AM
Patricia Feager, MBA, CRS, GRI,MRP
DFW FINE PROPERTIES - Flower Mound, TX
Selling Homes Changing Lives

Walt Fish - It is a pleasure to meet you here on ActiveRain. I'm definitely following you. There is nothing more frustrating than to receive a home inspector's report and not know what it means. Thank you for explaining a common problem that I see often and learning just how serious this can be.

As a person who once lived in Northern, IL, I had a house fire started by an electrical fire that started with arcing and I had aluminum wiring in my home built in 1972. The fire didn't occur until 1994 and I was lucky my son and I survived when it caught fire on a cold and freezing day in January. The Fire Marshal said we were very, very lucky because the wires inside were burning for a long time. Then, when I mentioned the issues I was having with my electrical appliances and the furnace it all made sense. 

Feb 19, 2018 09:44 AM
Walt Fish
Bay Area Home Inspection, LLC - Marquette, MI
Upper Michigan's Most Experienced Home Inspector

Thanks Patricia! Following you as well. Yes, Aluminum had similar problems as double lugging in that the wires would sometimes work a bit loose and cause arcing. It sounds like you were very lucky.  

Feb 19, 2018 10:26 AM

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