from todays inspection

[John Dirks Jr]

Not only is the main supply line leaking at the joint between PE and PVC, they have galvanized connected to copper doing its expected corrosive reaction. It's before the main shutoff as well. Top that off with the main electrical ground connected to the copper portion of supply pipe. It's useless as a ground when you have a plastic main line in from the street.

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[David Meiland]

You're saying there are no ground rods and no Ufer ground, and that the electrician connected to the water line as a way of grounding the house??

[John Dirks Jr]

You're saying there are no ground rods and no Ufer ground, and that the electrician connected to the water line as a way of grounding the house??

No. There is rebar extending from the foundation floor. You can see that in the corner of the first pic. The question is, is that sufficient? Rebar is not the best material for a ground rod, is it? With the lack of a good path to ground from the conductor in pic 3, I think the resistance of the rebar should at least be tested to see if its good enough. What do you think?

1996 construction.

[Jim Katen]

You're saying there are no ground rods and no Ufer ground, and that the electrician connected to the water line as a way of grounding the house??

No. There is rebar extending from the foundation floor. You can see that in the corner of the first pic. The question is, is that sufficient? Rebar is not the best material for a ground rod, is it? With the lack of a good path to ground from the conductor in pic 3, I think the resistance of the rebar should at least be tested to see if its good enough. What do you think?

1996 construction.

The connection to the water pipes is the bonding connection. It doesn't provide grounding, it bonds the copper piping system to the service so that the copper can't become energized. It's required.

The rebar is probably a concrete encased electrode, more often called a Ufer ground. It works very well and has been required for a long time even though many areas have been slow to adopt the idea. It provides an excellent connection to the earth because of the large area of concrete in contact with the soil.

Look for a proper connection between the grounding electrode conductor and the rebar. There are only a few types of clamps that are approved for that connection.

[John Dirks Jr]

Thanks Jim,

I knew gas pipes were required to be bonded but I did not know the water piping required a ground.

My bad.

[John Dirks Jr]

To be straight forward about it, I'm embarrassed that I didn't realize the connection was for bonding rather than grounding. I should know that as it's basic stuff.

Obviously, I need to brush up on my system grounding and bonding requirements.

Any suggested material that focuses in on these?

[hausdok]

To be straight forward about it, I'm embarrassed that I didn't realize the connection was for bonding rather than grounding. I should know that as it's basic stuff.

Obviously, I need to brush up on my system grounding and bonding requirements.

Any suggested material that focuses in on these?

Yeah,

Electrical Inspection Of Existing Dwellings - 2001 Edition by Douglas Hansen.

You've heard us say it here before; now I'll say it again and all of you others that don't have it, GET IT!!!

Don't spend a dime on any more kewl flashlights, IR thermometers, moisture meters, etc., until you've purchased a copy of that book. Once you've got it, read it cover to cover. Then read it cover to cover again. Then put it in the throne room and read something in it every time you have to, uh, er, ponder your place on this planet.

There isn't another book about electrical that I've every read that broke it down and explained it better. If you don't get that book, you ain't serious about this biz.

ONE TEAM-ONE FIGHT!!!

Mike

[Chad Fabry]

The rebar is probably a concrete encased electrode, more often called a Ufer ground. It works very well and has been required for a long time even though many areas have been slow to adopt the idea. It provides an excellent connection to the earth because of the large area of concrete in contact with the soil.

As I understand it, it is required only if there is steel in the foundation, and for existing structures, only if the steel is accessible.

You should have heard the whining the first time I told the mason to bend a rod up.

[John Dirks Jr]

Doug's book is on the top of my shopping list.

[Marc]

Doug's book is on the top of my shopping list.

It seems to be in short supply.

Chad, on a house without a basement, can the connection to the ufer ground be done hidden from view within a wall cavity?

Marc

[hausdok]

Doug's book is on the top of my shopping list.

It seems to be in short supply.

Chad, on a house without a basement, can the connection to the ufer ground be done hidden from view within a wall cavity?

Marc

I can answer that. It must be done in a way that you can view it. I remove covers to confirm ufers and bond connections all the time.

ONE TEAM - ONE FIGHT!!!

Mike

[David Meiland]

For a Ufer ground, we're not allowed to connect the EGC to rebar here (WA State Labor & Industries inspects electrical work here). The copper wire has to be run into the footing and clamped to a 20' length of bar (sometimes interpreted as multiple piece(s) spliced together with tie wires, sometimes interpreted as one uncut 20' piece). I specifically have to get the electrician to come out and clamp the copper to the rebar before we pour, and then get that inspected or in rare cases provide a photo of it. Later, he connects that same copper to the panel.

[Nolan Kienitz]

UFER grounds are becoming "suspect" down here (Texas) as when a foundation is set out the pads are covered with 6-mil poly and then the pour begins.

It is putting a layer of 6-mil poly between the earth and the encased electrode in the beam.

Not a good thing overall.

Some AHJ's are requiring other methods in light of that from what I've been hearing.

[Chad Fabry]

Chad, on a house without a basement, can the connection to the ufer ground be done hidden from view within a wall cavity?

No, although the connection can be made in a standard box with a labeled cover.

250.68 Grounding Electrode Conductor and Bonding Jumper Connection to Grounding Electrodes.

The connection of a grounding electrode conductor at the service, at each building or structure where supplied by a feeder(s) or branch circuit(s), or at a separately derived system and associated bonding jumper(s) shall be made as specified 250.68(A) and (B).

(A) Accessibility. All mechanical elements used to terminate a grounding electrode conductor or bonding jumper to a grounding electrode shall be accessible.

Exception No. 1: An encased or buried connection to a concrete-encased, driven, or buried grounding electrode shall not be required to be accessible.

Exception No. 2: Exothermic or irreversible compression connections used at terminations, together with the mechanical means used to attach such terminations to fireproofed structural metal whether or not the mechanical means is reversible, shall not be required to be accessible.

[Jim Katen]

For a Ufer ground, we're not allowed to connect the EGC to rebar here (WA State Labor & Industries inspects electrical work here). The copper wire has to be run into the footing and clamped to a 20' length of bar (sometimes interpreted as multiple piece(s) spliced together with tie wires, sometimes interpreted as one uncut 20' piece). I specifically have to get the electrician to come out and clamp the copper to the rebar before we pour, and then get that inspected or in rare cases provide a photo of it. Later, he connects that same copper to the panel.

There's nothing wrong with that method but it's not necessarily any better than running a stick of rebar above the concrete and clamping to it. I'm wondering why WA state decided to go that direction.

[Jim Katen]

UFER grounds are becoming "suspect" down here (Texas) as when a foundation is set out the pads are covered with 6-mil poly and then the pour begins.

It is putting a layer of 6-mil poly between the earth and the encased electrode in the beam.

Not a good thing overall.

Some AHJ's are requiring other methods in light of that from what I've been hearing.

Those must be monopours. So you have plastic under your footings?

[charlieb]

Same here in MS. Monolithic and everything has plastic under it. So, I've never seen a ufer.

[Jim Katen]

Same here in MS. Monolithic and everything has plastic under it. So, I've never seen a ufer.

If there's plastic under the footing, then you can't do a Ufer. The concrete must be "in direct contact with the earth."

[charlieb]

Yep.