UFER Ground

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O

olly

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Berthoud, Colorado
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Master Electrician
Is a ufer ground needed in a monolithic concrete pour? I dont know much about how these are poured. Take for instance a barn. I dont think they put any rebar in so is a stubbed out rebar / not connected to any other rebar do any good. Do inspectors still like to see a rebar stubbed for ufer connection?
 
In a barn with livestock, you will need an equipotential plane installed in addition to a ufer.

A monolithic pour still requires a ufer, as the buildings foundation is still in contact with the earth below grade, similar to a footing and stem wall.
 
infinity said:
If there is no rebar then no Article 250 CEE is required.
Click to expand...
I don't agree, if there is not any rebar then you have to put 20 feet of bare copper per 250.52(A)(3)(2).

(3) Concrete-Encased Electrode. A concrete-encased elec‐
trode shall consist of at least 6.0 m (20 ft) of either (1) or (2):

(1) 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, installed in one
continuous 6.0 m (20 ft) length, or if in multiple pieces
connected together by the usual steel tie wires, exother‐
mic welding, welding, or other effective means to create a
6.0 m (20 ft) or greater length; or

(2) Bare copper conductor not smaller than 4 AWG
Metallic components shall be encased by at least 50 mm
(2 in.) of concrete and shall be located horizontally within that
portion of a concrete foundation or footing that is in direct
contact with the earth or within vertical foundations or struc‐
tural components or members that are in direct contact with
the earth. If multiple concrete-encased electrodes are present
at a building or structure, it shall be permissible to bond only
one into the grounding electrode system.
Informational Note: Concrete installed with insulation, vapor
barriers, films or similar items separating the concrete from the
earth is not considered to be in “direct contact” with the earth.
 
Strathead said:
I don't agree, if there is not any rebar then you have to put 20 feet of bare copper per 250.52(A)(3)(2).

(3) Concrete-Encased Electrode. A concrete-encased elec‐
trode shall consist of at least 6.0 m (20 ft) of either (1) or (2):

(1) 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, installed in one
continuous 6.0 m (20 ft) length, or if in multiple pieces
connected together by the usual steel tie wires, exother‐
mic welding, welding, or other effective means to create a
6.0 m (20 ft) or greater length; or

(2) Bare copper conductor not smaller than 4 AWG
Metallic components shall be encased by at least 50 mm
(2 in.) of concrete and shall be located horizontally within that
portion of a concrete foundation or footing that is in direct
contact with the earth or within vertical foundations or struc‐
tural components or members that are in direct contact with
the earth. If multiple concrete-encased electrodes are present
at a building or structure, it shall be permissible to bond only
one into the grounding electrode system.
Informational Note: Concrete installed with insulation, vapor
barriers, films or similar items separating the concrete from the
earth is not considered to be in “direct contact” with the earth.
Click to expand...
No, that section tells you what is permissible as a grounding electrode & what a CEE is.
If a CEE is not present, you don't have to install one.
Ron
 
rc/retired said:
No, that section tells you what is permissible as a grounding electrode & what a CEE is.
If a CEE is not present, you don't have to install one.
Ron
Click to expand...
That's correct. You are not required to create a CEE if there is not 20 or more feet of 1/2" or larger rebar in the footing.
 
rc/retired said:
No, that section tells you what is permissible as a grounding electrode & what a CEE is.
If a CEE is not present, you don't have to install one.
Ron
Click to expand...
Again disagree, if a footer isn't present then you don't have to install a CEE. If a footer is present whether it has rebar in it or not, it needs to have a CEE.
 
The language in 250.52 states if available at the premise served, the following shall be used for the GEC.
If there is no rebar, then a CEE is not present.
 
Strathead said:
Again disagree, if a footer isn't present then you don't have to install a CEE. If a footer is present whether it has rebar in it or not, it needs to have a CEE.
Click to expand...
How would one compliantly connect to a footer with no metal in it?
 
Strathead said:
Again disagree, if a footer isn't present then you don't have to install a CEE. If a footer is present whether it has rebar in it or not, it needs to have a CEE.
Click to expand...
That is incorrect. Footings without rebar or with rebar that is less than 1/2" in size and or less than 20' in length do not require using a CEE.
 
infinity said:
That is incorrect. Footings without rebar or with rebar that is less than 1/2" in size and or less than 20' in length do not require using a CEE.
Click to expand...
In other words, if the footer, as it is constructed, does not qualify it as an electrode, there is no requirement to convert it into one.
 
LarryFine said:
In other words, if the footer, as it is constructed, does not qualify it as an electrode, there is no requirement to convert it into one.
Click to expand...
Correct and if there is no electrode present you are not required to make one by installing 20' of #4 or larger copper.
 
If any of you are on the International Residential Code (IRC):
R403.1.7 Grounding electrodes. When concrete reinforcing
bars are installed in concrete footings, the following
requirements shall be met to provide for a grounding
eletrode system:
1. Uncoated No. 4 reinforcing bar installed not less than
3 inches (76 mm) from the bottom of the footing and
not less than 20 feet (6096 mm) in length encased with
a minimum of 2 inches (51 mm) of concrete.

2. An uncoated No. 4 reinforcing bar stubbed up at least
12 inches (305 mm) above the floor plate line and
tightly attached to the reinforcing bar located in the
footing. The spliced lap of the stubbed up bar to the
footing bar shall be a minimum of 12 inches (305 mm).
Click to expand...
 
Living in California I can't imagine a footing without rebar. On may projects I would swear there is more steel than concrete in the footings, walls and slabs.
 
This is certainly an interesting discussion. I agree that if there is no reinforcement steel required in the foundation than no CEE is present, nor is it required to be. That being said, why wouldn't you want to add it? Even if it's not required it's a relatively inexpensive upgrade that would add strength to the foundation, and CEE's are a far superior grounding electrode... But technically not required.
 
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