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Yes, all domestic buildings in the US have their own earth ground, and this is and has been required by the NEC (National Electrical Code). Often this is a thi

Yes, all domestic buildings in the US have their own earth ground, and this is and has been required by the NEC (National Electrical Code). Often this is a thick, 8-foot long copper rod pounded into the ground not far from the electrical panel, connected to the panel by a ~1cm diameter copper cable. (There are other allowed methods, including using a similar copper electrode encased in concrete or in the building foundation.) It looks like this (which shows a galvanized-steel rod rather than the more canonical copper, and shows a further connection to a second ground rod, which is not required everywhere): http://www.wireyourownhouse.com/panel/images/grndrodexample.png http://www.wireyourownhouse.com/panel/images/grndrodexample.... Also, certain sub panels (e.g., in garages) will need their own separate earth ground, made the same way. This "grounding electrode" is in addition to a connection ("bond") to the domestic cold-water pipe, usually done where the pipe enters the building. (That pipe itself may be a hunk of copper buried in the ground.) The electrical bond to the water service is not a substitute for the dedicated grounding electrode mentioned above, it's to ensure that the plumbing does not become electrically charged.

mattrp 7y ago
All except homes built many years ago where someone felt it was satisfactory to clamp a single wire to the water line. I’ve seen this numerous times. Not to mention the numerous instances of 20A breakers on 14awg. It’s simply amazing what one will find in some homes... like the person who clipped both ends of an extension cord to feed an outlet out of a junction box rather than spend $20 on home wiring. Or the person who literally covered a chiseled-out trench in plaster with painters tape to conceal wire. And on and on...
- bcrosby95 7y ago
  > where someone felt it was satisfactory to clamp a single wire to the water line. I’ve seen this numerous times. Our house was built in the 70's and that is what we used to have. After we upgraded our panel though we got not 1, but 2 grounding rods.
  - mturmon 7y ago
    According to this thread [1], it was the 1978 code that required a dedicated grounding electrode. That's 40 years ago, but of course many houses have not been upgraded since then, and some localities might not have adopted the 1978 NEC until later. [1] https://forums.mikeholt.com/forum/active-forums/nec/86062-code-year-for-ground-rods?t=135832 https://forums.mikeholt.com/forum/active-forums/nec/86062-co...
  - mattrp 7y ago
    2 is what I’ve installed in the houses I’ve renovated. It’s just not worth the risk to your electronics and home itself to cheap out on proper electrical in your house. Particularly if you’re one of those people with a 12 core 20tb dell r720 in the basement.
chrisdhoover 7y ago
Adding a ground to water pipe is a bad practice. With no hub rubber connectors it may not even work. It is also dangerous for any working the pipe
- mturmon 7y ago
  This is incorrect. In general, in the US, it is required to bond a metallic water pipe system (e.g., copper or galvanized pipe) to the electrical grounding system. This is usually done near the service entrance so that the connection can be verified by direct inspection. For (much) more on this, see: https://iaeimagazine.org/magazine/2005/11/16/bonding-metal-piping-systems/ https://iaeimagazine.org/magazine/2005/11/16/bonding-metal-p..., in particular the paragraph starting “Let’s take a closer look” — “If metal water piping systems are not bonded to the electrical system in a way that meets the requirements of the Code, they can present a fire or shock hazard within the building or structure because they could become energized. ...” In some jurisdictions, inspectors may want you to bond around nonconductive plumbing connectors of the kind you mentioned to ensure the whole pipe system is bonded. In particular, around the hot water heater.
js2 7y ago
Yellow-jacketed CSST (corrugated stainless steel tubing used for natural gas) must also be bonded. This was added to the code in the mid-2000s so homes built from the mid-nineties when CSST became available till around 2005 when bonding requirements for it were added may not have it. I had to retrofit it to my 2004 home. https://structuretech1.com/csst-bonding-requirements-final-update/ https://structuretech1.com/csst-bonding-requirements-final-u... http://csstsafety.com/csst-faqs.html http://csstsafety.com/csst-faqs.html
sgc 7y ago
All modern concrete foundations are required to have a Ufer ground[1] installed, and this Ufer is required to be connected to the panel. So ground rods are rather obsolete in most circumstances. But as others have noted, it would be better to have an impedance test during the dry season. [1](https://en.wikipedia.org/wiki/Ufer_ground https://en.wikipedia.org/wiki/Ufer_ground)

mattrp 7y ago

All except homes built many years ago where someone felt it was satisfactory to clamp a single wire to the water line. I’ve seen this numerous times. Not to mention the numerous instances of 20A breakers on 14awg. It’s simply amazing what one will find in some homes... like the person who clipped both ends of an extension cord to feed an outlet out of a junction box rather than spend $20 on home wiring. Or the person who literally covered a chiseled-out trench in plaster with painters tape to conceal wire. And on and on...

bcrosby95 7y ago
> where someone felt it was satisfactory to clamp a single wire to the water line. I’ve seen this numerous times. Our house was built in the 70's and that is what we used to have. After we upgraded our panel though we got not 1, but 2 grounding rods.
- mturmon 7y ago
  According to this thread [1], it was the 1978 code that required a dedicated grounding electrode. That's 40 years ago, but of course many houses have not been upgraded since then, and some localities might not have adopted the 1978 NEC until later. [1] https://forums.mikeholt.com/forum/active-forums/nec/86062-code-year-for-ground-rods?t=135832 https://forums.mikeholt.com/forum/active-forums/nec/86062-co...
- mattrp 7y ago
  2 is what I’ve installed in the houses I’ve renovated. It’s just not worth the risk to your electronics and home itself to cheap out on proper electrical in your house. Particularly if you’re one of those people with a 12 core 20tb dell r720 in the basement.

chrisdhoover 7y ago

Adding a ground to water pipe is a bad practice. With no hub rubber connectors it may not even work. It is also dangerous for any working the pipe

mturmon 7y ago
This is incorrect. In general, in the US, it is required to bond a metallic water pipe system (e.g., copper or galvanized pipe) to the electrical grounding system. This is usually done near the service entrance so that the connection can be verified by direct inspection. For (much) more on this, see: https://iaeimagazine.org/magazine/2005/11/16/bonding-metal-piping-systems/ https://iaeimagazine.org/magazine/2005/11/16/bonding-metal-p..., in particular the paragraph starting “Let’s take a closer look” — “If metal water piping systems are not bonded to the electrical system in a way that meets the requirements of the Code, they can present a fire or shock hazard within the building or structure because they could become energized. ...” In some jurisdictions, inspectors may want you to bond around nonconductive plumbing connectors of the kind you mentioned to ensure the whole pipe system is bonded. In particular, around the hot water heater.

js2 7y ago

Yellow-jacketed CSST (corrugated stainless steel tubing used for natural gas) must also be bonded. This was added to the code in the mid-2000s so homes built from the mid-nineties when CSST became available till around 2005 when bonding requirements for it were added may not have it. I had to retrofit it to my 2004 home. https://structuretech1.com/csst-bonding-requirements-final-update/ https://structuretech1.com/csst-bonding-requirements-final-u... http://csstsafety.com/csst-faqs.html http://csstsafety.com/csst-faqs.html

sgc 7y ago

All modern concrete foundations are required to have a Ufer ground[1] installed, and this Ufer is required to be connected to the panel. So ground rods are rather obsolete in most circumstances. But as others have noted, it would be better to have an impedance test during the dry season. [1](https://en.wikipedia.org/wiki/Ufer_ground https://en.wikipedia.org/wiki/Ufer_ground)