Are older houses with ungrounded 3 prong outlets installed a safety hazard?

Question

We're looking at buying a house. Because of the age of the house 2 prong receptacles are throughout the house. But there are a bunch of 3 prong receptacles installed at various locations that are not grounded. To change the 3 prong to grounded receptacles an electrician would have to ground the entire house which means re-wiring the entire home. Should we still buy this house?

The seller says they will not re-wire the entire home. The 3 prongs can be used, but they just won’t be grounded. If you have them put the 3 prong back the 2 prong then you won’t be able to use a 3 prong appliance unless you use adapters.

I guess my question is would it be safe to use the 3 prongs without grounding or to put the 3 prongs back to 2 prong?

I'm wondering if we should go ahead with buying this house.

Any advice would be appreciated.

Answer 1

The ground wire is wired into your panel to the same connection that the white wire is connected to. It is mearly a better means of grounding the home in the event of a failure. Most new homes now require this through National Electrical Code. You are not required to install the upgrade unless a permit is pulled for an addition, or other renovation. This addition then would have to meet code. I am not an electrician, but I work with a lot of them. I believe this is correct.  

Answer 2

Three wire circuits are the minimum now for new construction.  This house needs to be upgraded either by the seller or you after you buy it.

Answer 3

How old is the house. It may be a simple matter of replacing the outlets. In a lot of older homes the ground is at the box and can be connected easily. You can buy a cheap outlet tester and an adapter to test this. Good luck!

Answer 4

Buy the house because it's the one you like and can afford.  If an inspector says the wiring is good just old, I wouldn't worry about updating.  As far as safety goes...  Just be careful of what you plug in.  

Answer 5

The seller is wrong.Code say's that if there is no grounding conductor in the box then you have to use either two prong outlets,or gfci outlets, or protect the three prong outlets with a gfci breaker and label each outlet no grounding conductor.Check to see if the metal boxes that holds the outlets is grounded.

Answer 6

USA    The short answer is, at one point the receptacles will need to be changed to three prong receptacles.  Many sensitive devices (computers for example) will not function 100% okay without the ground.  And appliances with a metal housing, if not grounded, can be hazardous.  It would "shock" you to find out how often that happens.

BUT, the house might not have to be re-wired.  If the house was wired with non metallic sheathed cable (romex) with a ground, the receptacles can be upgraded NO PROBLEM.  If the house was wired in BX (metal covered) and the outer metal covering was not destroyed, the receptacles can be upgraded NO PROBLEM - the metal covering is the ground.  But, it must be continuous from the metal receptacle box (not plastic) to the breaker panel, and it is best to install a ground wire from the receptacle to the box.

If the house was wired with the k**b and Tube method, there is NO WAY you will get a proper ground, and yopu cannot legally install three prong receptacles.

If the wiring is the only thing holding you back from buying the house, do one of two things:  Plan on having it totally rewired for at least $5K, or up to $8K for a big house, or call a licensed electrician, and get a professional opinion.  You will probably have to (and should) pay the electrician for the opinion.  A reputable electrician will want to get your future business, so they will not jack up the price or scare you.  If you pay for their opinion, and they know up front you might not buy the place, they have nothing to lose and will give you an honest opinion.

DO NOT listen to friends, family, etc... unless they are electricians.

Answer 7

Calm down.

Those plugs were in there since the '50's and nobody died.

If the house is '50's vintage, there's a good chance that you do have a grounded system via 'BX' (armored), cable and steel junction boxes.

It's a relatively simple matter to ground those receptacles to the boxes.

Look for visible wiring at the panel in the basement.

If you see cable with spiral steel wrapping, you're OK.