An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!

wrote in message
...
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite
certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!


Generally speaking 24" is minimum for UF (18" for one and two family homes)
and 18" for PVC. EMT is not permitted for direct burial however rigid
galvanized is. If a 120 volt, 20 amp circuit is GFI protected it is
permissible to run the wire at 12". I don't recommend the lesser depth or
the use of a GFI to protect the entire run of wire as it will be more
subject to nuisance trips. For more details look up table 300.5 in the
National Electrical Code.

In article , wrote:
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite certain
this does not meet code.

Yep, you're right, doesn't meet the National Electrical Code (NEC).

Understand, however, that your local jurisdiction may have requirements that
differ from the NEC, so for the definitive answer regarding what's legal where
you live, call your local electrical inspector. The local requirements can be
either more stringent than the NEC (Chicago, for example) or less so (certain
areas of rural Indiana, for example -- I used to live in a place where there
was _no_code_at_all_. Scary.)

I always did my wiring to Code even though there was no legal requirement to
do so, and if I had an electrician working for me, I'd insist he do the same.

Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Having said all that, though, here's what the NEC says about minimum
cover for buried electrical installations (assuming that we're talking about
burying it in your yard, not under a driveway, sidewalk, basketball court,
etc):
- direct burial: two feet
- in rigid nonmetallic conduit (PVC): eighteen inches
- in EMT (aka thinwall) -- don't know -- can't find that listed
- in Rigid Metal Conduit (aka thickwall) or Intermediate Metal Conduit: six
inches

Note also that if the circuit is 120V, *and* not more than 20A, *and*
protected by a GFCI, it may be as shallow as twelve inches (six if in RMC or
IMC).

But under *no* circumstances does it meet Code to direct-bury a UF cable as
shallow as only four inches.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , "John Grabowski" wrote:

wrote in message
.. .
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite
certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!


Generally speaking 24" is minimum for UF (18" for one and two family homes)
and 18" for PVC.

I don't find the exception for one and two family homes in the 2005 NEC.

EMT is not permitted for direct burial

John, do you have a Code cite for that? I'm not disputing you, I'm curious. I
didn't think it was permitted, either, but I couldn't find anything that said
one way or the other. Article 358.10(B) says it's permitted "in direct contact
with the earth" but doesn't mention burial; but 358.12 does not list burial as
a use not permitted.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

But under *no* circumstances does it meet Code to direct-bury a UF cable as
shallow as only four inches.

Code aside, that fails to even meet common sense requirements. If
someone could snag it with rototiller, it is way too shallow.

"Doug Miller" wrote in message
...
In article , "John Grabowski"
wrote:

wrote in message
.. .
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite
certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!


Generally speaking 24" is minimum for UF (18" for one and two family
homes)
and 18" for PVC.

I don't find the exception for one and two family homes in the 2005 NEC.



Table 300.5 Column 1, 6th row. Now that I read it again it might be for
only under driveways.




EMT is not permitted for direct burial

John, do you have a Code cite for that? I'm not disputing you, I'm
curious. I
didn't think it was permitted, either, but I couldn't find anything that
said
one way or the other. Article 358.10(B) says it's permitted "in direct
contact
with the earth" but doesn't mention burial; but 358.12 does not list
burial as
a use not permitted.



Doug you are right. It can be construed from 358 that it is permissible to
direct bury EMT. It's something that I have never done nor do I recall ever
seeing EMT put directly in the ground. I'm not sure what fittings one would
use. Raintight?

Doug Miller wrote:
In article , wrote:
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite certain
this does not meet code.

Yep, you're right, doesn't meet the National Electrical Code (NEC).

Understand, however, that your local jurisdiction may have requirements that
differ from the NEC, so for the definitive answer regarding what's legal where
you live, call your local electrical inspector. The local requirements can be
either more stringent than the NEC (Chicago, for example) or less so (certain
areas of rural Indiana, for example -- I used to live in a place where there
was _no_code_at_all_. Scary.)

I always did my wiring to Code even though there was no legal requirement to
do so, and if I had an electrician working for me, I'd insist he do the same.

Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Having said all that, though, here's what the NEC says about minimum
cover for buried electrical installations (assuming that we're talking about
burying it in your yard, not under a driveway, sidewalk, basketball court,
etc):
- direct burial: two feet
- in rigid nonmetallic conduit (PVC): eighteen inches
- in EMT (aka thinwall) -- don't know -- can't find that listed
- in Rigid Metal Conduit (aka thickwall) or Intermediate Metal Conduit: six
inches

Note also that if the circuit is 120V, *and* not more than 20A, *and*
protected by a GFCI, it may be as shallow as twelve inches (six if in RMC or
IMC).

But under *no* circumstances does it meet Code to direct-bury a UF cable as
shallow as only four inches.


Not quite true. When UF is used to run low voltage wiring supplied
through a laboratory listed power limited supply it can be run at quite
a shallow depth of bury. That's the problem with these types of
questions. We have to assume so much to answer them.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison

Doug Miller wrote:
In article , "John Grabowski" wrote:
wrote in message
...
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite
certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!

Generally speaking 24" is minimum for UF (18" for one and two family homes)
and 18" for PVC.

I don't find the exception for one and two family homes in the 2005 NEC.

EMT is not permitted for direct burial

John, do you have a Code cite for that? I'm not disputing you, I'm curious. I
didn't think it was permitted, either, but I couldn't find anything that said
one way or the other. Article 358.10(B) says it's permitted "in direct contact
with the earth" but doesn't mention burial; but 358.12 does not list burial as
a use not permitted.



It is permissible to bury EMT when it has corrosion protection suitable
for conditions. The inspector is likely to require you to wrap the EMT
in protective tape. There is PVC clad rigid conduit that is both
better protection and more corrosion resistant. If you don't need the
metal raceway for some good electrical reason such as noise protection
for communications circuits then Rigid Nonmetallic Conduit (PVC) is the
way to go.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison

varies by location, wet/dry climate, building zoned use, earthquake
zone. [?]

wrote:
An electrician is burying an unprotected UF-B wire on my property. In
places it is approximately 4" (yes inches) below grade. I am quite certain
this does not meet code. Can anyone tell me:
Minimum depth for buried wire w/no conduit
Minimum depth with electrical PVC Conduit
Minimum depth with electrical emt Conduit

Thanks!!

In article , "John Grabowski" wrote:

"Doug Miller" wrote in message
t...
In article , "John Grabowski"
wrote:
Generally speaking 24" is minimum for UF (18" for one and two family homes)
and 18" for PVC.

I don't find the exception for one and two family homes in the 2005 NEC.

Table 300.5 Column 1, 6th row. Now that I read it again it might be for
only under driveways.

Right, just "driveways and outdoor parking areas."


EMT is not permitted for direct burial

John, do you have a Code cite for that? I'm not disputing you, I'm curious. I
didn't think it was permitted, either, but I couldn't find anything that said
one way or the other. Article 358.10(B) says it's permitted "in direct contact
with the earth" but doesn't mention burial; but 358.12 does not list burial as
a use not permitted.


Doug you are right. It can be construed from 358 that it is permissible to
direct bury EMT. It's something that I have never done nor do I recall ever
seeing EMT put directly in the ground. I'm not sure what fittings one would
use. Raintight?

I imagine so, since EMT is approved for use in wet locations with suitable
fittings and corrosion protection. Just the same, I don't think I'd use it.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Not quite true. When UF is used to run low voltage wiring supplied
through a laboratory listed power limited supply it can be run at quite
a shallow depth of bury. That's the problem with these types of
questions. We have to assume so much to answer them.
--
Tom Horne

It still fails the common sense test, a few years from now someone will
want to put in a flower bed and destroy the entire install with one
pass with a rototiller. Granted no harm will come to them if it is low
voltage, but some folks actually like to have installed stuff stay
installed.

I don't recommend the lesser depth or
the use of a GFI to protect the entire run of wire as it will be more
subject to nuisance trips.

Why would it be subject to nuisance trips?

I don't recommend the lesser depth or
the use of a GFI to protect the entire run of wire as it will be more
subject to nuisance trips.

Why would it be subject to nuisance trips?

I was about to ask the same question.

I have all kinds of circuits (including exterior lighting -- my household
wiring is a hodgpodge) which I protected with GFCIs for "belt & suspenders"
purposes. An older ice box (1975? model occasionally popped a GFCI on
defrost and a dishwasher that had a leak likewise occasionally tripped a
GFCI.) Exterior lighting just hasn't tripped it either.

I have even left an extension cord plugged into a GFCI and after a rain
storm the cord is still hot. (Not every time, but yes, I tested the
GFCI.)

I not longer believe in nuisance trips. If a GFCI trips either the GFCI is
messed up or there is something really wrong that can and should be fixed.