How to Replace Electrical Wiring

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Remember these pictures from last week? (If not, I LOVE that you looked right away, but I posted it and then thought of an even better example–so the old post is revamped)

There is ONE outlet above the oven on this entire wall. The other one is reserved for the range.

There are TWO outlets on this entire wall.

Time to make some changes replacing and adding some new wire!

DISCLAIMER:

I used my brother’s expertise, who had already passed city inspections on his own house. I also worked with a local licensed electrician who I hired to evaluate the work and worked with the city. Electricity is a big deal. Do it right with the proper code and great guidance to pass your inspection with flying colors. If you do not feel comfortable DO NOT do this job. Hire it out. It is not worth burning down your house.

Now let’s talk about how to replace electrical wiring along with some gritty details on making your own job easier.

How to drop a home run.

A home run is a electrical wire that extends all the way from the panel to the first outlet or switch in one shot (no splicing with junction boxes).

When you are replacing an old line, expect to replace all gangboxes. Once you remove the new work gangbox with a sawzall you have a nice gaping hole with the old wire(s) hanging out. Attach the new wire on the coil to the old wire by hooking each wire with each other.

Next, duct tape both ends together.

Tell your counterpart in the attic to start pulling. They will gently and slowly pull the old wire out bringing the new wire up.

I mention gently because there are often snags. The joint you just created can get caught on the header joist in the wall right at the ceiling. Sometimes there is a fire break stud horizontally placed halfway up the wall and the hole is small.

Keep in mind, when the house was built there was no drywall so the original electrician had insanely easy access. Did they need to make the hole any bigger than necessary? No.

This is why you want to make the loop/tape joint as thin and strong as possible. You do not want to think about what happens if the old and new wires become separated at any point in the middle of the wall where there is no access.

Once the new wire is above the wall in the hands of the schmuck in the attic they can take the old wire off the new wire. Next, they will pull the new wire across the attic to the ceiling above the panel and drop the line through.

Make sure there is enough extra wire dropped before cutting the wire off back in the original spot where the coil is located:

• The wire should be able to reach the panel with extra length for maneuvering the wire in the box.
• If you do not have a walkway in the attic you may want one at some point so do not make the wire taught. Give it a little play to allow it to go around anything you may want to install later.
• Make sure you have about 8 or so inches hanging outside the hole where a new work gangbox will go. Extra wire is needed at a later time if you want to change an outlet for any number of reasons (you want a new color, childproofing your outlets by replacing them with new tamper resistant outlets, etc.). Spare wire neatly folded into the box allows you (or the next homeowner) to change your mind several times before you run out of wire.
• Label the wire in the attic as well as in the room before it enters the panel. You will thank yourself later if you have to do any maintenance.

How to run a jump

Within a circuit each outlet, switch, or light will piggyback off the long run from the panel. If another wire is piggybacking off the first hole to another circuit or outlet, then repeat the same attachment process to the new wire. The only difference is heading to the next drop instead of the panel.

Repeat again, and again, and again…

Tip #1: Get the BEST help you can find to teach you how to replace electrical wiring.

Family, friends, licensed contractors, books and TV are all possible options. I used them all!

Contractors…

My husband and I went over the plan with the electrician marking out the locations of new outlets. They checked our work mid project and at the end when the hooked up the panel to the main.

Family and friends…

My brother and I made an agreement. He would teach me how to wire my house while I would teach him how to tile at his house. It was a win-win. Neither of us would have to spend time learning an extra trade and I love tiling. So, he drove down with my parents and I flew him back after a few days of his of learning from his expertise.

The minute my brother arrived we were in a world of wires, gang boxes, circuits, light switches, outlets, outlet and light switch covers along with a shiny new 200 amp panel.

You name it, we installed it. All of it. Even the accursed pain-in-the-you-know-where-to-install 8-3 oven wire.*

Although victorious after an hour, I was too mad at the dumb wire and all the lost time to smile. Your hair can look this amazing too after spending quality time in the attic during the summer.

Books…

After my brother left (and even while he was there) we referred to circuit diagrams in the Complete Do-It-Yourself Manual. This book is a great resource for all kinds of house projects–not just tile and electrical.

TV…

If you have ever watched Holmes on Homes, you know what Mike Holmes tells you about hidden junction boxes. Having watched my fair share, I could hear him in the back of my mind as we ran each home run. If the wire is not long enough you can use a junction box as a connection point to connect the short piece with another length of wire to make it to the intended destination.

We did not use a single junction box.

Instead, the shorter pieces at the end of the roll were used on the shorter runs right by the panel. Or use them on lines daisy chaining off the home run.

Which brings us to the next point…

Tip #2: Maximize the each coil and save yourself from having to buy an extra roll.

Option #1: Run the long runs first. Shorter runs are a better use of the end of the roll(s) of wire. It stinks to hit the end of the coil mid run and this method minimizes this problem.

Option #2: Really nerd out and make an excel spreadsheet to maximize the usage of each roll of wire. Measure out the distance from the panel to the ceiling, the length of wire in the ceiling from the panel to the drop point, and the drop point in the ceiling to the outlet, switch or light. I am not suggesting you cut each piece before trying to run the wire because it would suck if you needed six more inches after cutting off 60 feet of wire. Instead, run the wires in order of longest to shortest, then cut each wire after you make the drop. This is a great way of knowing which runs you will make with each coil.

While I’ve done option #2 on baseboard, I went with Option #1 for this electrical project.

Tip #3: Get someone you love (or hate) to help you run the wires.

This is not a solo job. When you are replacing home electrical wire someone is in the attic and the other person is downstairs at the end of the old wire. If you don’t like someone send them into the attic and they will never bother you again. 😉 Only someone who loves you will stick around.

Technical lessons learned while replacing the electrical life blood of a house:

• Once you have the new line in place it is time to attach an outlet or light switch. When you attach the new wire to an outlet or light switch make sure to bend the ground wires to go the same direction as tightening the screw. Let’s physics work for you! If you have the wire pointed the wrong way it is more likely to unwrap itself as you are making the last turns to tighten it down. If this is the case, the final connection is not as good as it could or should be.
  

  The right direction.

  

  A good connection.

• Keep an electrical diagram map. It is a lifesaver when you want to turn a circuit off quickly. If you don’t you will end up standing outside in the dark (because that’s when we do these projects, right?) with a flashlight staring blankly at each circuit trying to interpret the labels. Once you start experimenting by turning each circuit off at the panel you end up taking twice as long because you have to remember how to reset every clock in your house. It is also super annoying if you are running “which circuit is this outlet on” and “how many times can I walk back and forth” game by yourself. A diagram eliminates the guesswork. BONUS: your neighbors won’t think you’ve lost it.
• Email the electrical diagram to yourself so you always have it handy. Of course, the minute you need it somehow it disappears… In true nerd fashion I added keywords so I would not have to remember if the subject was electrical diagram or whatever I was thinking at the time: “Other keywords: Electrical, electric, house.”
• This ridiculous sized wirecutter saved much cursing and time when cutting the larger wires, like the oven, A/C, washer and dryer wire. It also works in a pinch if you misplace your hand saw when you need to cut back your palm tree fronds.
• If you did not read the last post make sure you check out the lighthearted, but VERY REAL lessons learned at the end. I guarantee you will laugh in agreement on at least a few points.
• Too true that I had to copy it from the last post: Once you have the seal of approval from the electrician, the city agrees, the power is on, the appliances are running, and nothing is on fire it is official: YOU ARE A BADASS.

*There are different size (gauge) wires. The size you want depends on the needs of the appliance at the end of the circuit. A toaster oven obviously runs on much less power than an electric range. Of all wires in a house, the wire for an electric range oven is the worst.  Quite honestly, when I was fighting the wire into the circuit I didn’t know who was going to win–me or the wire.