CEE Rebar Stub Out? I don't think so.

[tryinghard]

81+ posts all because of 250.4(A)(1), I really don't mean to minimize this too much though.

But hay your NEC compliant if you have your general labor wire tie 40 pieces (chunks) of 1/2" rebar into one big bundle; as long as it is near the bottom of a footing and has at least 2" of concrete around it. :roll:

I?ll just install my #4cu electrodes and bond the rebar whatever the rebar does or is, I don?t even care if the rebar is driven in dirt.

 

[e57]

~~~I don’t even care if the rebar is driven in dirt.

It might even fly if 5/8"D and 8' in the dirt - depending on the AHJ - so long as Bob hasn't brain washed them first. (edit to add: You might need two of them... )

(5) Rod and Pipe Electrodes. Rod and pipe electrodes shall not be less than 2.5 m (8 ft) in length and shall consist of the following materials.
~~~
(b) Electrodes of rods of iron or steel shall be at least 15.87 mm (5/8 in.) in diameter. Stainless steel rods less than 16 mm (5/8 in.) in diameter, nonferrous rods, or their equivalent shall be listed and shall not be less than 13 mm (1/2 in.) in diameter.

The placement of the period, IMO means steel or iron rods 5/8" or > don't need to be listed, 1/2", Stainless or AL ones do.....

 

[cschmid]

You really lost me.

In a nut shell any part of the re-bar that is not encased in at least 2" of concrete is not IMO an NEC electrode, it is just re-bar.

So a re-bar stubbed out of the footing is just re-bar not a CEE. :smile:

It states "An electrode encased by at least 50 mm (2 in.) of concrete, located horizontally near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth"

so if the NEC calls Re-bar an elctrode..yet it actually states what type of material needs to be used..

"consisting of at least 6.0 m (20 ft) of one or more bare or zinc galvanized or other electrically conductive coated steel reinforcing bars or rods of not less than 13 mm (1/2 in.) in diameter,"

So the stub sticking out of the concrete is legal..

Now back to the question you are confused about..re-bar is just thrown in the footing on at grade slab..they are not stacked up of the ground so as to be encased in 2 inches of concrete..some times the concrete guys reach down and jerk up on the re-bar and allow the concrete to get under it.yet they wheel wheel borrows on it..So is the re-bar really encased in 2 inches of concrete just because the slab is 4 inches thick does not ensure that..the only place you can ensure that the re-bar is encased in 2 inches of concrete is on an elevated slab..So does the elevated slab meet the requirements of a CEE..

I believe it does not because it is not in contact with the earth..so the only reason the CEE is any good whether it is encased with 2 inches or less of concrete is because it is in contact with the earth..

 

[crossman]

It states "An electrode encased by at least 50 mm (2 in.) of concrete, located horizontally near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth"

so if the NEC calls Re-bar an elctrode..yet it actually states what type of material needs to be used..

"consisting of at least 6.0 m (20 ft) of one or more bare or zinc galvanized or other electrically conductive coated steel reinforcing bars or rods of not less than 13 mm (1/2 in.) in diameter,"

So the stub sticking out of the concrete is legal..

I just don't catch the logic here.

I don't have any problem with using a rebar stub-up for the GEC attachment, but literally, it is a violation of the NEC IMHO.

 

[mayjong]

come on!
nobody uses slab reinforcement as an electrode, you are really reaching now!
every CEE i've seen has been in a footing, not touching the dirt (as ALL reinforcement should be.) i wouldn't accept slab reinforcement for the same reasons. (not to mention it calls for the CEE to be in a "concrete foundation or footing , which a slab is not)
if the NEC didn't allow it , it wouldn' have included "accessible connection" and 250.68

 

[cschmid]

I just don't catch the logic here.

I don't have any problem with using a rebar stub-up for the GEC attachment, but literally, it is a violation of the NEC IMHO.

I guess what I am saying here is that if the rod meets all the rquirments and there is 20 ft encased in concrete and the end sticks out of the cement then it is legal..

 

[tryinghard]

If you have a slab-on-grade that includes a footing and its outside dimensions are 200? x 50? for a building, and you choose to connect your GEC to the bottom rebar in the footing that is greater than ?? diameter, and if this rebar at 250 lineal feet away is 1 ?? from the earth you in fact do not have your GEC connected to a NEC electrode! Or if the rebar guy ran out of tie wire and used some forming string...same problem not an electrode as per NEC. Nobody looks at these that close.

If you simply install 20? more of your GEC in this same scenario you would have your GEC connected to a compliant NEC electrode! Bond it to the rebar anyway it may help the resistance.

 

[cschmid]

come on!
nobody uses slab reinforcement as an electrode, you are really reaching now!
every CEE i've seen has been in a footing, not touching the dirt (as ALL reinforcement should be.) i wouldn't accept slab reinforcement for the same reasons. (not to mention it calls for the CEE to be in a "concrete foundation or footing , which a slab is not)
if the NEC didn't allow it , it wouldn' have included "accessible connection" and 250.68

What is re-bar if not slab reinforcement..and if the slab is a floating slab no footings..that equals slab foundation..

 

[cschmid]

Here when you get to job site you have a stub out installed by who ever did the concrete..unless you are in an area that inspects the concrete pours you really never know if it is correct or not..

So how do you guys handle it..when you are contacted to wire the place and the slab and part of the structure is already there..you have a stub out to connect to..is it legal to use it..

 

[crossman]

To answer your question, it is necessary to know what other electrodes are present?

 

[cschmid]

good point..you are going to add the other electrodes do you count the stub out as your CEE or do you drive the second rod..

 

[jflynn]

[So how do you guys handle it..when you are contacted to wire the place and the slab and part of the structure is already there..you have a stub out to connect to..is it legal to use it..[/QUOTE]


In MA. as IWIRE has shown in earlier post,G.C;s were copied on documentation regarding the use of CEE and its need to be installed.If you have arrived @ a jobsite and there was a stub out to connect to would you just attach to it not knowing if it actually qualifies to be used?did the form guys just stick a piece of re-bar out the side or top of the foundation wall?this is why i have to say it should be done in the footing and inspected before it is poured-The stub out method is not the intent of the NEC..

 

[crossman]

And on another note: Say you are the EC and the foundation and footings contain nothing but non-conductive epoxy coated steel rebar. Is it necessary for the EC to install an electrode in the foundation or footings?

 

[mayjong]

cschmid-
are you talking about a slab with turned down footings?
i have never seen a slab (3 1/2" thick concrete) used as a foundation for house without a perimeter footing. (at least not in the last decade)
of course i'm in CA , and we tend to build a little different here. if it was a slab with no footing, it would be technically impossible to meet the requirement (unless the slab was 4 1/2" thick min)

tryinghard-as far as the reinforcement 250' away being 1 1/2" from dirt (assuming the rest is compliant) that is a joke.
talk about " show me in the code" !?!?!? i would be laughed off the jobsite if i wrote that. i guess because the last 10' of a 250' CEE is not compliant the whole thing fails?!?!?!
i agree with e57 -the period seperates the the two - making the argument mute. along with 250.68 . along with "accessible connection".
if you can use an accessible connection with a driven rod , then you can with a CEE.

edit - for content off topic

 

[cschmid]

I do not remember saying a 3 1/2 inch thick slab they are 4 1/2 in thick and as you called it a turned down footings..

the only time I see these is reality is when I see a cabin built by the HO in steps as the foundations are cheaper to have poured..other wise you see them allot in garages, out building and the like..Normally you see footings on the house itself..

So the HO has the garage built and pours the slab as we have mentioned..HO want EC to install the service meter on the garage.. they want to live in it while they build their new house..so you are required to use the CEE or drive 2 rods..You have the CEE stubbed out do you use it or drive 2 rods and ignore it..

edited to add: I think I can see some revisions coming to this area of the code..

 

[mayjong]

i would say if there is reinforcement in the "turned down footing" then you have a CEE. stub it out and attach to it.
btw- the only slabs we see here over 3 1/2 " thick are structural slabs and post- tension slabs , which are a whole other ball game.
perimeter footings are required on all buildings in CA (i know, i know ,there are some cases where they are not used, like on the coast, where DEEP pilings are used , but other than that...) so there is always a footing for the CEE.

edit for clarity

 

[mayjong]

So the HO has the garage built and pours the slab as we have mentioned..HO want EC to install the service meter on the garage.. they want to live in it while they build their new house..so you are required to use the CEE or drive 2 rods..You have the CEE stubbed out do you use it or drive 2 rods and ignore it..
..

for this, if i never saw it, i can't approve it (or the use of it....)
we inspect all foundations in CA , though

edit for clarity

 

[cschmid]

I throw this out there because bob was going for the wording and the stub out being Illegal..there is allot of loop holes in the CEE and I am not for sure if it is the correct avenue for grounding requirements..no different then driving 2 rods we are not automatically achieving a low resistance ground..

considering the ground is only really for 2 things; 1-is to protect from excessive voltage surges.. 2- stabilize the voltage on the transformer (again controlling the incoming power surges)

I really do not believe in a smaller voltage transformer you could ever operate a OCPD through the ground conductor..

 

[tryinghard]

tryinghard-as far as the reinforcement 250' away being 1 1/2" from dirt (assuming the rest is compliant) that is a joke.
talk about " show me in the code" !?!?!? i would be laughed off the jobsite if i wrote that. i guess because the last 10' of a 250' CEE is not compliant the whole thing fails?!?!?!

:grin: Ha! :grin: Ha! :grin: Ha! :grin: Ha! :grin: Ha! :grin: Ha! :grin: Ha! :grin: Ha!?

I don't think you should leave your job but your right, it's not code compliant.

Kinda like losing the status of an electrode that protrudes out of a footing, semantics but true.

 

[tryinghard]

tryinghard-as far as the reinforcement 250' away being 1 1/2" from dirt (assuming the rest is compliant) that is a joke.
talk about " show me in the code" !?!?!? i would be laughed off the jobsite if i wrote that. i guess because the last 10' of a 250' CEE is not compliant the whole thing fails?!?!?!

And all the electrician needs is 20 more feet of #4 on the GEC!?!?!?