The following info explains how part of your electrical system in your home works. It is not meant to be a guide for DIY repairs. Do not touch any part of your electrical system if you are not qualified to do so. You CAN DIE FROM THIS STUFF. Please do not be dumb. Call a pro and let them handle it.
It never fails. At least once a week I inspect a house that has an ungrounded electrical system. These are older homes with receptacles (or outlets, as everyone in my neck of the woods calls them) that only have two slots, and are missing the ‘3rd hole.’ That hole is for the ground conductor of the circuit. The grounding conductor wasn’t introduced until ~1962 in Louisville, KY. So if you live in an older home, that hasn’t been upgraded to modern electrical safety standards, chances are your system is ungrounded too – or at least part of it is. This could be true even if you have modern 3-hole outlets installed. I get a lot of deer-in-headlights looks when I start to talk about this stuff at my home inspections, so let me break things down for you here, and explain what all this means.
Determining if you have ungrounded outlets
Most of the time, you can simply look at your outlets and see if you still have the old ungrounded style or not. If you only see two vertical slots, they are ungrounded. However, I see lots of older houses where folks will replace their outlets with new (modern, 3-hole) outlets to make it easier to plug grounded cords in. Of course, this doesn’t make things “grounded,” you simply lose the frustration of having to use one of those cheater adapters that have the ground pin missing. If you are unsure if your receptacles are grounded, you can pick up a cheap outlet tester and it will tell you if you have a ground connected at the outlet. My receptacle tester that I use during home inspections is way more sophisticated as a circuit analyzer, but in this case essentially reports the same info: is there a ground present at the outlet. You can see an example of this in the picture below. I’m plugged into a 3-hole outlet in a 90 yr old house, but the ground icon (center light) is not lit up. This is an ungrounded 3 hole outlet.
OK, my outlets are ungrounded – Why should I care?
First, let’s briefly run through how electricity in your home works; more specifically, how the outlets work when something is plugged into them. The most important thing to remember is that electricity flows in a circuit, and it’s always trying to get back to the source. The electrons flow from the hot side of an outlet, through the device that is plugged into it (toaster/vacuum/hairdryer/etc), and back through the neutral wire to the panel (or the source.) The device you plug into the outlet completes the circuit between the hot and the neutral wires, and electricity flows through the device to run a motor, heat some coils, or whatever is needed. That is a basic 120v circuit. Pretty simple. Notice I did not bring up the use of a ground wire at all…
The hot wire is connected to the electric panel via a circuit breaker (or fuse, if your system is really old). The breaker is in place to trip (kill the power) if it senses the current flow is too high in the circuit. (This is why it’s important that your breakers be sized correctly for the wire it’s protecting.) If the breaker sees an abnormal amount of current flowing through it, it trips and shuts down the power. When a breaker trips it is known as a fault. The fault must be found and “cleared” before things can return to normal, and you can turn the power back on.
As you can see from the above example, a ground wire is not needed for a 120v circuit to function. In fact, there are lots of things you plug into your electrical system that doesn’t use the 3rd pin at all. Lamps, cell phone chargers, and toasters only have two prongs on their cords. However, there are lots of other items in your home that do utilize the ground as a safety measure. Things like refrigerators, washing machines, computers, and TVs have grounded cords. The grounded cords typically show up on items that have a metal case or have sensitive electronics inside them.
Having a fully grounded electrical system is all about safety. It’s a safety measure put in place for you, your house, and your stuff that is plugged into/connected to your house. In fact, the “ground” we are talking about is technically known as an equipment ground. There are system grounds (power company side of things), and equipment grounds (your house side of things). Everyone around here (and I would imagine many other places) just calls it a ground, so we’ll stick with that.
Grounding is in place to protect us from faults (bad things within an electrical circuit) and damage from lightning strikes. Faults just happen. Electrical motors go bad, wires break, etc. Lightning strikes also get filed under “it happens.” According to NOAA, there are 25,000,000 cloud-to-ground lightning strikes every year. Let’s break down some examples of why equipment grounding and grounded outlets are important to you and the safety of your family.
While not perfect, this video does a good job of explaining the history and progression of the electrical system in homes in the U.S.
When things go wrong
The ground wire in an electric system is in place to send rogue current safely back to the electric panel (or the source). In the event of a problem within the circuit, the ground wire provides a path for the current to safely make it back to the panel to trip the breaker or blow the fuse.
The following are some examples of what can happen when dealing with an ungrounded electrical system – especially ungrounded outlets. What you want to keep in mind is that these things occur when bad things happen. Grounding is not needed when life is good and things are rolling on as they should be. Think of it like an airbag in your car. You can drive all day every day and never need your airbag. It’s when bad things (like a wreck) happen that you sure are happy to have that safety device.
When something goes wrong in an electrical circuit, we call that a fault. We now use grounded circuits to help protect us from these faults. Example: Let’s say we have a refrigerator plugged into an ungrounded outlet. If a wire inside the unit were to touch the metal case of the fridge- the case is now conducting the current. It’s very possible the resistance will be low enough that the breaker will not trip. You come along to grab a cold beer after a hard day of crawling through attics and crawlspaces, you could get electrocuted. No one should have to choose from getting shocked, or getting a beer, btw.
Surge protectors when used in an ungrounded house are nothing more than really cool looking extension cords. They can not protect your equipment from surges without the ground wire. That is how they work- they use the ground wire to safely remove the spike or surge in voltage. The warranty on your stuff they brag about when using their product goes out the window too when used on an ungrounded outlet.
1 out of every 200 houses will be struck by lightning. This is according to the National Lightning Safety Institute. Lightning is an extremely powerful, high-frequency blast of DC voltage, which is capable of devastating damage when you get hit by a direct strike. However, you do not have to suffer a direct hit to have bad things happen. When lightning hits the ground it pushes electrons in all directions. If your house happens to be close enough to this strike, the voltage can jump to the building. This is known as side flash. Now that stray voltage is in the building (on the plumbing pipes, in the wires, etc.) We ground the house to help this voltage get to where it wants to go….the earth (or ground). In other words, we connect all the conductive materials in the house and terminate them to a single point- the ground rod near the electrical panel, or other means (like a water pipe that runs through the yard.)
Side flash is what happens when an indirect lightning strike happens and the stray voltage from the strike jumps to conductive things inside the house (like plumbing parts and wiring). If you happen to be standing close to one of these things like an ungrounded outlet, or a steel post in your basement, it could jump over to you and cause you to become electrocuted.
Take the same concept as above with side flash, but you place a combustible material in the mix and you could have a house fire. Even worse, you get electrocuted, you burst into flames, and it sets your house on fire. Hey…it could happen.
Watch this video for a couple of minutes. Mike does a great job of explaining things equipment grounding in a building.
Grounding can save your bacon if things go south one day. There is a good reason the process has been required in homes since 1962. I know some of this sounds scary to folks, and while I don’t want to promote fear, I do like to promote education and respect for something that can kill you in the blink of an eye. But all is not lost. When it comes to getting this issue taken care of, there are options. In future posts, I’ll break down those for you, and explain how all that works. Check back soon…
System Grounding is NOT a protective measure against a direct lightning strike on your home. If you suffer a direct strike, that small bare copper wire will not save you. Grounding of an electrical system should not be confused with lightning protection. The bottom line with a direct lightning strike near or on the house—you simply have to fix whatever gets broken or bury whoever dies.
When I’m performing a home inspection on a house built around 1970, I usually get the question, “Does it have aluminum wire?” Let’s talk about what the issue is, and what your options are if you are looking to buy a house that has aluminum branch wiring in it.
What are branch circuits?
Branch circuits are circuits that power the “small” stuff like your lights, outlets, and small machines (think dishwasher, disposal, etc.) Aluminum wiring was first used as branch circuits around 1965 during a copper shortage, and was used in homes until the mid 1970’s. It’s the small 15 and 20 amp breakers in your electrical panel. The larger wires (usually 240v stuff) and the main power lines coming into the home are typically aluminum but do not have any issues.
Facts about Aluminum Wiring
The Consumer Product Safety Commission (CPSC) released a “Repairing Aluminum Wiring” pamphlet that you can download here. Don’t be foolish and try to use it as a how-to guide. It’s meant to explain what can be done by an electrician who knows what he or she is doing. Here are some interesting facts for you:
- There are an estimated 2 million homes wired with aluminum wire.
- The problem is the connection points and splices at junction boxes, outlets, switches, etc.
- A national survey conducted by Franklin Research Institute for CPSC showed that homes built before 1972, and wired with aluminum, are 55 times more likely to have one or more wire connections at outlets reach “Fire Hazard Conditions” than homes wired with copper.
- On April 28, 1974, two people died in a home in Hampton Bays, N.Y. Fire officials determined that the fire was caused by an overheated aluminum wire connection at a wall receptacle.
When I find aluminum wiring, it seems I always get the question, “Do you think it will be a problem?” Another popular thing I hear is “If it hasn’t been an issue in 40 years, it probably won’t ever be one.” Wait….what? People downplay the issue in their minds because of the scope of the potential problem. It’s not convenient for them to have to deal with this right now. But it is real, and it can’t be ignored.
What are the issues anyway?
Aluminum wiring has several unique traits that its copper counterpart does not. All of these add up to the reason it’s no longer used.
- Aluminum is Soft – When you tighten the set screw down on an outlet or switch, the aluminum wire will actually continue to flatten out a bit over time – even after you stop torquing the screw. This will cause a loose connection. Loose connections cause arcing. Arcing causes fires.
- Thermal Movement – Everything moves with temperature. Aluminum wire is no different. When the wire has electrical current flowing through it, it heats up. When it heats up it expands. The issue is that aluminum expands more than copper. Over time this swelling and shrinking can cause a loose connections. Again, arcing and fire.
- Oxidation – When aluminum wire is exposed to oxygen it oxidizes. This byproduct is called aluminum oxide. This stuff can deteriorate the connection.
- Corrosion – When moisture is added to the mix of aluminum wire, you get galvanic corrosion at the connections.
I have aluminum wire. Now what?
The first thing you do is get an electrician experienced with aluminum wiring to come check every connection they can possibly get to in the house. Will they be able to check them all? Doubtful. Most houses have junctions behind drywall or in the attic we can’t see or know they are even there. According to the rules, there should never be concealed junctions, but the reality is that people don’t always obey the rules. Having ol’ sparky come check things out can be pricey, but his house call is much cheaper than a house fire.
What can be done to minimize the risk?
There are several products on the market designed to help minimize the risk when dealing with aluminum wiring.
1. One of the more popular products I find people know something about are the specially rated outlets and switches made for aluminum and copper wires. These are marked with a CO/ALR on them. CO=copper – ALR=Aluminum. Would you know to get these for your house if you had aluminum wire?
Here is a scenario for you:
Being the hip, young couple that you are, you’re ready to tackle some DIYing this Saturday. So your normal Friday movie date is replaced with a shopping trip to Lowe’s. You get your paint, brushes, tape, flooring and so on. Your better half proclaims those ugly almond outlets have got to go in lieu of some nice new white ones. No worries, right?
You stroll to the electrical aisle and reach for those shiny white outlets. You need 5 for the living room. Better get 6, just in case. How much? $.68 cents. No sweat.
You grab your 6 outlets and start to walk away. Out of the corner of your eye you see another receptacle that looks identical to the one in your hand, except it’s almost $4 bucks. What? $4 for one! I don’t think so. Let’s roll babe.
2. There are special connectors called AlumiConn available. These are approved by the CPSC, but at nearly $4 each, they are not a cheap option. Understand that is $4 per wire; per connection.
3. Another product is the COPALUM connector. This system uses a special clamp, crimping tool, and heat-shrink to create a copper pigtail off the aluminum wiring. You must be certified to use this system. Some areas don’t have anyone available who is certified in using the COPALUM system.
4. Total Replacement of the aluminum wire itself. This is, of course, the safest of all options. It is also the most expensive. Cost will vary, as every house is different in the process used to replace the wire. You’ll need to speak with an electrician to get an idea of what you can expect. Keep in mind this is typically thousands of dollars. It’s not a cheap process.
If you have aluminum wiring in your home, you need to get that electrician out there ASAP. If you are not sure if you have aluminum wiring or not, a reputable home inspector in your area should be able to come out and take a look for you. You shouldn’t take the cover off of your electrical panel yourself unless you know what you are doing. There are things in there that will kill you.
You have options in what can do. You can repair or replace. Either is better than nothing at all. And when it comes to situations like this; it’s never a problem until it becomes one.
WARNING – THE FOLLOWING GIVES INSTRUCTION ON HOW TO WORK ON PART OF THE ELECTRICAL SYSTEM IN A HOME. IT IS TECHNICAL IN NATURE AND NOT MEANT FOR EVERYONE. IF YOU DO NOT FEEL COMFORTABLE TAKING YOUR LIFE INTO YOUR OWN HANDS, OR POSSIBLY DAMAGING YOUR HOME, READ ON, AND THEN CALL A PRO.
I’ll let you in on a little secret. Insulating your home is only half the battle when it comes to saving money on your energy bills. The other half, and some would argue the most important, is that you must air seal the outer walls/ceiling. This is also known as the building envelope. We must stop air movement from the living space and the outdoors too.
The Science Of Building Heating and Cooling
In physics, the second law of thermodynamics says that heat flows naturally from an object at a higher temperature to an object at a lower temperature; and heat doesn’t flow in the opposite direction of its own accord. This means hot moves to cold on its own. In the winter, your hot air air is trying to escape the house, and in the summer, the hot air outside is trying to get in. It’s a never ending battle. Every little crack and hole in your house is a path to losing money, comfort, and is making your furnace/air conditioning work harder.
Take a Peek
Behold the beautiful wonder of thermal imaging! I love my thermal camera. It has made me a hero more times than I can count during my home inspections. Thermal Imaging Inspections take inspecting to a whole new level. You can see in the image below, an electrical outlet in my house. I’ve marked the hi and low temps to make it easier for you to understand the colors. The blue area is all the cold air leaking in around the edge of the electrical box, and the holes where the wires come into the box.
Stopping these leaks is a small piece of a larger puzzle, but still a piece nonetheless. The first thing you do is kill the power to whatever you are working on. Don’t try any of this on a live circuit or you could electrocute and kill yourself. Don’t be stupid. Now that you’ve turned off the power you’ll want to remove the receptacle itself. GENTLY pull it straight back and out of the box. If the person who wired your house left the wires too short in the box to safely pull the receptacle up and out of the way, stop now. You could pull the wires off the receptacle, break a wire, etc… Call in a pro to have your wires extended. If you can pull out your receptacle and it looks like the image below, carry on.
Seal It Up
Now that we can work without fear of breaking wires and/or electrical shock, I use caulk and expanding foam to seal the box. Using a high quality painters caulk, caulk the edge of the electrical box to the drywall itself. I got lucky and the drywallers did a decent job of cutting out for my boxes, so the gap is not very large. Your mileage will vary on how much caulk it takes to seal this up.
Now that the box-to-drywall connection is sealed, let’s focus on the wire penetrations. You may have one, two, or even three sets of wires coming into the box itself. This number will vary on how outlets/switches are in your box. Treat them all the same here. I have two sets of wires coming in to deal with. A small shot of spray foam around each wire is all it takes. You can see here how the foam will spread itself around the wires and seal them up.
Expanding foam in the disposable cans can get pricey. Once you crack the seal on them the clock starts before it becomes useless. Remember, a little goes a long way with expanding foam. This stuff will grow and grow once you squirt it out. If you get trigger happy and get too much in the box; just let it cure and dig it out. Don’t try to touch it wet. You’ll just end up with a sticky mess on your hands. One can will likely do your whole house. So if you have to buy these types of cans, you may want to tackle the whole house at once to save on foam.
Here is another thermal image pic showing the improvement we made. This area is a full 6.1 degrees warmer. But more importantly, we have stopped the airflow from getting into the living space of the house. That airflow cost money and comfort 24-7-365.
But Ben, why is the area still blue and cold you ask?
Understand that what we are working on is air sealing of this box , not the insulation around it. We are still seeing cold temps and blue coloring because the insulation around this particular box is non-existent. This receptacle is above my fireplace where most builders do not attempt to insulate. I”ll tackle the insulation another time.
This procedure is good for just about every penetration in your home’s envelope. All your receptacles, light switches, hard wired smoke detectors, ceiling lights, ceiling fans, and any other hole you may have. It’s a quick process. Takes me about 2 minutes per box to seal it up, and you reap the benefits instantly.
I’m a bit later than I wanted to be getting this written, but hey, better late than never. If you missed the first part of this post you can see it here: Best of Home Inspections 2014. So without further ado, the second half of the Best of the Worst pictures of 2014.
A waterfall in the crawlspace – This house was about 15 years old. This was the 3rd person selling it. What you are looking at is the master shower that was NEVER connected to the home’s plumbing. It has been dumping shower water under the house since the day it was built. How many other inspectors missed this little gem because it was in a tight spot that took a bit of extra effort to get to? And do you know what I had to craw through to see it? Go on…tell me you’ve never peed in the shower.
NEW Insulation in the Attic – That is what the listing boasted. In fact, the buyer even commented to me on how this flipper (not the dolphin) did everything just right. I may be a bit cynical, but I have never seen a flipped house “done right.” When I climbed through the tiny hole in the ceiling to get into the attic I saw this pile of batt insulation (the worst possible choice for attic insulation, mind you). Well…in the sellers defense, there was new insulation in the attic, it just hasn’t been installed yet.
Leaning Crawlspace Tower of Pisa – Truth be told, I could make one of these post every week with the crap I find in crawlspaces alone. This beauty was in an old house, circa 1900. There were probably a dozen or so of these wonderfully crafted modern marvels scattered throughout. What do you say other than “Um…no.”
Air filters are important – Who doesn’t like clean, fresh air? The people who owned this house, that’s who. This was a 10yr old gas furnace that I don’t think has ever had a filter installed it. I was getting very little air flow out of it and when I took the unit apart I found this fan so clogged with crud it could barely draw the air through it.
Casting a shadow – It doesn’t hurt to turn off your ceiling fans every few years and wipe them down. The dust on the edge of this fan blade was nearly 3/4 inch thick. So fellas, the next time you start to catch heat about not pulling your weight in the house cleaning department, just show the them this pic and point out how it could always be worse.
My last and final picture is not of a house, but of a fortune cookie message I received a few weeks ago. It only took 30 years to get one that actually made sense.
I’ve got enough pictures to write a novel of funny, awful, and scary things I’ve found during my home inspections, and I’ve already started compiling my list for next time. I had record numbers in 2014 because of you and the trust you put in me. I love what I do, and I love helping people. Thank you for choosing ABI.
Another year older, one or two more gray hairs found, and a stack of pictures to choose from. It’s hard to whittle it down to just a handful, but I selected the top 10 problems found during home inspections this year. A Cold Fireplace – This is a picture from a one year old home. The owners […]