Renting at a place where 3-prong outlets not grounded properly

July 4, 2005 9:33 PM

My wife and I recently rented a house in the Phinney Ridge area of Seattle. When renting I saw that all of the outlets were 3 prong outlets and that there was a breaker box and not a fuse box, so I assumed it was all wired correctly. Now that we've moved in, I've found that 6 of the 10 outlets are coming up as "open ground" when using a grounding tester.

It looks like the 4 most important outlets (i.e. the ones near water in the kitchen and bathroom) are grounded properly.

The ones that are affected are in the living room and bedrooms and will have mostly computers and stereo equipment plugged into them. Pretty much all of it consists of 2 prong equipment, but the surge protectors all have 3 prongs and the manufacturer’s website state that not having a working ground "may affect the surge suppression capability".

From what I can tell, the outlets don't have conduit going to them, so I'm guessing that just attaching the ground wire to the outlet’s box won't help at all.

I've e-mailed the landlord and they sent a reply saying that they'd "look into it", but I'm not sure if that means that anything will get done, or how quickly it will happen. I’ve been hesitating to get all of our stuff set up here as I don’t want it all to get fried if something happens.

Is this something I should be worried about, or is it not really a big deal for the outlets that are affected? If my landlord decides that it's not a big deal, should I try to get this fixed myself or is it pretty low risk?

If left alone, is there a big risk of electrocution, or of my stuff getting fried with the first thunderstorm to come our way?

Related question that doesn't quite answer my question here.

posted by freshgroundpepper to home & garden (13 comments total)

Check out GFI (Ground Fault Interrupter) outlets, also mentioned in your linked thread. Grounding is not necessary for GFI outlets; they function by detecting differences in amperage between the hot and neutral wires. When these amp levels are not equal, the GFI device assumes a safety problem and instantly disconnects the power.
But don't rely on internet advice--consult an electrician.
posted by weapons-grade pandemonium at 10:22 PM on July 4, 2005

Chances are that a real electrician has never seen the wiring in that house and the landlord has no intention of ever sending one. To give you some perspective, my mother recently purchased a house that's entire second floor was knob and tube wiring. Some of the outlets on the second floor had their polarity reversed and none of them were grounded. The cost of replacing the wiring was far to expensive, considering that the only thing you have to watch out for is well, nothing she has encountered so far.

The outlets in the bathroom and kitchen really should be GFIs and not just grounded regular outlets but local codes vary and I have no idea what they are like in Seattle.

As for risk, I wouldn't have ever bothered to check to see if they were grounded. I fact, outside of home inspections that are made during the purchase of a home, I don't think that anyone ever checks them. The only thing I would worry about is grounding the outlet that will power your surge protector.

Keep in mind that I am just some random guy on the internet- not a licensed, insured and bonded electrician- that has now absolved himself from any responsibility should things go wrong while following his advice.
posted by 517 at 10:35 PM on July 4, 2005

In terms of surges, it really depends how settled your area is. Not living in Seatle, I have no idea about that. If you are in the city proper I would guess that you have no need for a surge suppressor at all.

Ground can sometimes be helpful in terms of EMI (noise) suppression, but sometimes it makes things worse, so...

As for electrocution issues... I don't know how familiar you are with electricity (if you aren't familiar with it you should be). The electrical wiring faq is great, and it covers exactly this topic too.

background:
To be electrocuted your body must be touching objects at two different voltages (like ground and a live wire). You have to be completing a circuit for current to be able to flow, just touching a high voltage won't do anything to you (think about birds on high tension wires). This is why the greatest electrocution hazard in a household is between AC mains and plumbing (of course any grounded metal will do, copper water pipes are most common, iron drain pipes and the metal chassis of a stove are good candidates too).

In a room that doesn't have any grounded metal at all (like a living room with no grounded outlets), the only electrocution hazard is between two devices that expose you to different potentials. This would require an independent failure in each of two devices.

Many places suggest that a ground fault interrupter (GFI) can add electrocution protection in places where a ground conductor isn't available (the linked faq says this, for example). GFIs are great protection in kitchen and bathroom (where ground exists due to copper pipe, some drain pipe, the special outlet for the stove, the steel gas pipe for a gas range). In a living room or bedroom without ground GFIs can't really do much of anything (of course somebody might introduce ground, with an extension cord for example, then the GFI might be useful again).

If the current that is causing you to be electrocuted is coming from and going back to the same GFI no imbalance will be sensed, and it won't trip. All the devices in your typical home theatre system are connected to the same plug... You should see the problem. On the other hand, if two independent failures have to occur before there is a hazard you are probably okay.

That doesn't actually answer the question... The only way to have an electrical system up to the standard of current building codes is to have it updated to comply with current building codes. That doesn't necessarily make the existing installation unsafe...
posted by Chuckles at 11:26 PM on July 4, 2005

517, it is easy enough to rewire the receptacles and get the polarity right, you should do it. At the very least label the ones that are backwards (no, I'm not saying a label would be 'good enough', but at least it is a start...).
posted by Chuckles at 11:34 PM on July 4, 2005

I wouldn't worry about it too much, as long as the kitchen and bathroom (and outdoor outlets if any --- basically anywhere there might be a nice watery path to ground) have working GFCIs. I've lived in the Greenlake, Ravenna, and UDistrict areas for fifteen years or so and have yet to experience anything recognizable as a power surge. We don't get all that much lightning here, after all.

It's hard to guess the safety of wiring based on its age or technology. I've seen ancient knob-and-tube wiring that looked as taut as the day it was installed and was probably as safe or safer than modern romex, and I've seen horribly installed modern-style wiring with dangling exposed conductors that I'm amazed didn't start any fires or kill people.

(But keep in mind that, like 517, I'm just some guy on the internet, with no particularly relevant credentials.)
posted by hattifattener at 11:46 PM on July 4, 2005

Thanks for the info guys. The FAQ that Chuckles linked to let me in on more info about how surge protectors work and why they need a ground to be able to function well.

It also talks about how a GFCI circuit will protect humans from getting electrocuted, but won't protect equipment from getting fried even with a surge protector. They really do need a ground to work properly.

What I'm getting out of all your help is that it's pretty unlikely in the locations that I don't have ground to actually get electrocuted, but that my stuff could potentially get fried as it essentially has no protection without ground.

Anyone have a guess as to how much it'd cost to have a few outlets rewired by an electrician so that they're grounded properly? (assume that they can't just be wired to the box that they're in, that's something that I can do myself)
posted by freshgroundpepper at 11:51 PM on July 4, 2005

ok, i'm no expert either, but isn't Chuckle's answer misleading and dangerous? the "background" section gives the impression that you can touch high voltages with impunity unless, in apparently exceptional circumstances, you are grounded. it also reads as though he's quoting something from the faq he linked to.

in fact, he's not quoting anything from the faq, and in my experience you'll always get a nasty shock from high voltages just through standing on the floor. you do not need to be touching pipes or another wire.

no doubt touching another (good) conductor makes things worse, and may provide a path through your body that's more likely to be dangerous (eg across the chest), but in practice you will always be grounded sufficiently to feel, at best, a hard jolt. and if you're unlucky (bad heart, or grab a wire in a way that means your convulsing muscles don't release it) it can kill.

if that's not right, someone please correct me.

also, and i think this is replying to someone else, while a circuit breaker will protect you, it's not going to help your surge breaker.
posted by andrew cooke at 5:11 AM on July 5, 2005

bleagh. "surge breaker" should be "surge or spike protector" or whatever they're called.

we had this place rewired, but since the work was part of more major alterations (and in another country) i can't give you a price. however, if you're lucky, new wires can be pulled through existing conduits. but given the state of american house wiring (based on questions here) i'm not sure you even have conduits.
posted by andrew cooke at 5:14 AM on July 5, 2005

Do you have a multi-meter? If so you can get an idea about how well it might work to ground the outlet using the ground wire on the box. (If you actually have a ground wire it should work.) Set the meter to AC to read 120V and read the difference between the neutral plug and the so called ground, in your case the box. This can be done by removing the faceplate. Be careful! If the grounded box and neutral are at the some potential - a zero volt differential - then grounding the outlet by wiring the ground to the box should work fine, otherwise you will have a floating ground which I doubt will protect your equipment. The grounding tab on a cheater plug works pretty much this way and if the potential between neutral and the faceplate screw is zero you can use the cheater with the grounding tab connected to the faceplate screw. This all assumes of course that the neutral and hot plugs are wired correctly.

On preview, as for touching high voltages, should be no problem as long as you are not grounded. Most electricians will not even shut the power to rewire an outlet and that work involves touching the hot wire. Don't touch more than one and wear nonconductive soles. I personally would never try such foolishness and if you electrocute yourself doing so than too bad for you and don't blame me, but it is done (by pros and fools).
posted by caddis at 5:45 AM on July 5, 2005

I don't know about any of this electrical stuff, but consider yourself lucky- we just found out a couple weeks ago that our FRIDGE wasn't even in a grounded outlet.
posted by elisabeth r at 6:47 AM on July 5, 2005

elisabeth r, that would be a perfect application for a GFI outlet! :)

andrew cooke, I agree, I do give the impression it was a quote. It isn't, I'm sorry, it was totally accidental. It happened while editing a huge amount of text... I was trying to give enough background to demonstrate my point about GFIs in 'non-conductive' rooms.

As for the correctness or, god forbid, danger - you are more or less completely wrong. You have to complete a circuit to be electrocuted. That can be accomplished in some very interesting ways - I expect wet concrete with rebar is pretty conductive - but there isn't much in a regular finished room to worry about. Anyway, it isn't surprising that I agree with myself, so I will have to let it go...
posted by Chuckles at 7:32 AM on July 5, 2005

i didn't say that the laws of physics were wrong. i said that you get sufficient grounding in most normal circumstances for it to be dangerous to rely on.
posted by andrew cooke at 7:34 AM on July 5, 2005

Anyone have a guess as to how much it'd cost to have a few outlets rewired by an electrician so that they're grounded properly?

I had a similar situation with a house that my wife and I purchased in West Seattle - all of the outlets in main floor looked normal, but in fact (as 517 noted) the were connected to knob and tube wiring in the attic. We paid an electrician to essentially pull new wiring from the circuit box to each outlet and to every overhead light (fixture) on the floor, through the attic.

We did this because insurance companies aren't happy with knob and tube wiring (an issue when buying a house), and because we can afford to pay a bit to be a little safer. The cost (for something like six fixtures and 12 outlets - I wasn't counting) was a couple thousand dollars (there was other work as well; didn't get the bill itemized), and, given the amount of time that the electricians actually spent working, I was afraid it was going to be a lot more.

Suggest: get an estimate (free) from an licensed electrician, then consider your options.
Under no circumstances would I recommend that you do any electrical work yourself.
posted by WestCoaster at 2:53 PM on July 5, 2005