A few quick observations from a master electrician with a 1964 house. First it's very unlikely that you have ungrounded wiring/outlets in your house. Almost always anything from 1960+ has grounds, there is a very small period that was during the 50/60's where they did run ungrounded wires, but it's pretty darn rare to find it anywhere. Look for a thinner ground wire, sometimes it was ran from the inside of the box to the connector screws on top/bottom of the metal box and screwed into the connector. This is not the best possible ground, but the ground is only there to trip the breaker in the case of a fault and otherwise does not serve any purpose. Sometimes it's not evident that they did it in this manner and you can verify by cutting a hole above the box (which would be covered by plate) and checking under connectors. It appears from your pics there may be a ground wire going under your box clamps, that may be your ground, again not the best, but serviceable.

If in fact your house had no grounds then yes, rewire. Very, very, unlikely.

As far as service size, I really doubt your draw 84 amps. Had a recent post on here that said the same, and based on size of home and info provided it was very unlikely. Only chance of drawing that kind of power is in all electric (no gas) home where your emergency heat is running. In that case about 100A with other louds running can be expected. 60-80a with just emergency heat and air handler fan only.

I could write paragraphs, getting on plane tomorrow. Will try to follow up tomorrow while bored at airport.

Just rewire the whole house with grounds and bond all that... two ground rods or equivalent... 1300 square foot house you should be okay and a hundred amp box should be fine.

I'd keep lights separate from wall outlets... wire the lights for 15 amps and use 14 gage wire and then use 12 gage for the plugs and 20 amp breaker....

this from me a non electrician who has done a lot of electrical work.

quote:

Originally posted by KevH:
The wiring in most of the house looks pretty d

I tested four outlets (different rooms) and an overhead light. All showed the metal boxes to be grounded.


Soooooo…..


Can I just screw a pigtail to the box and then to a GCFI in each outlet and put in an arc fault breaker for each circuit and call it a day?

The short answer is yes.

My house is exactly set up this way, all the runs to the metal boxes are BX cable and the boxes are grounded this way, with two-prong outlets. I've been slowly converting them to grounded, using the pigtail method.

You don't need GFCI's