Proper way to weatherproof direct burial service entrance conductors in foundation?

[JohnDS]

What is the proper way to weatherproof direct burial service entrance conductors coming through foundation underground with pvc sleeve?

I have seen people fill pvc sleeve with window foam. I have also seen it done with tar. I had also seen people use nothing.

What any of the first two methods be ok by themselves?
Will tar eventually break down the insulation on the wires?
What about weatherproofing on outside of the pvc sleeve, what would you use?
What is the proper way?

 

[Sierrasparky]

What is the proper way to weatherproof direct burial service entrance conductors coming through foundation underground with pvc sleeve?

I have seen people fill pvc sleeve with window foam. I have also seen it done with tar. I had also seen people use nothing.

What any of the first two methods be ok by themselves?
Will tar eventually break down the insulation on the wires?
What about weatherproofing on outside of the pvc sleeve, what would you use?
What is the proper way?

I think Duct seal or maybe some approved caulking .

 

[Gregg Harris]

What is the proper way to weatherproof direct burial service entrance conductors coming through foundation underground with pvc sleeve?

I have seen people fill pvc sleeve with window foam. I have also seen it done with tar. I had also seen people use nothing.

What any of the first two methods be ok by themselves?
Will tar eventually break down the insulation on the wires?
What about weatherproofing on outside of the pvc sleeve, what would you use?
What is the proper way?

230.8 Raceway Seal. Where a service raceway enters a building or structure from an underground distribution system, it shall be sealed in accordance with 300.5(G). Spare or unused raceways shall also be sealed. Sealants shall be identified for use with the cable insulation, shield, or other components.

 

[Little Bill]

230.8 Raceway Seal. Where a service raceway enters a building or structure from an underground distribution system, it shall be sealed in accordance with 300.5(G). Spare or unused raceways shall also be sealed. Sealants shall be identified for use with the cable insulation, shield, or other components.

While what you referenced to is correct, just placing a link like that to the code article doesn't help everyone. To use the link/site you must have a subscription. Not everyone has such a subscription. Just FYI.

 

[Volta]

Almost nothing will work for very long. I try any and all means available to penetrate a foundation underground.

That said, tar on the outside of the sleeve is pretty good. Duct seal around the individual wires is ok, but I think there are better sealants made to be in contact with the insulation out there.

 

[Volta]

Also, how is it allowed that there will be exposed conductors emerging from the sleeve once through the foundation?

 

[PetrosA]

Also, how is it allowed that there will be exposed conductors emerging from the sleeve once through the foundation?

This is how end boxes typically worked around here in towns and cities where the service came in underground from the street.

 

[Volta]

This is how end boxes typically worked around here in towns and cities where the service came in underground from the street.

Haven't heard that term before. Around here (Columbus) in the downtown network we install a "firebox" for laterals, a large enclosure with busbars for the utility and the premises wiring to individually connect to so no smoldering insulation can burn from a building into the underground utility ducts.

Is that like an 'end box'?

 

[Sierrasparky]

They do those fireboxe for single family res. too?

 

[Volta]

They do those fireboxe for single family res. too?

No, I don't think so. It is only downtown on that local network where there are few single-family units, if any.

Normally laterals in most of our sprawling metro area have no special provisions such as that. This is a utility rule also, not the AHJ's.

 

[Sierrasparky]

No, I don't think so. It is only downtown on that local network where there are few single-family units, if any.

Normally laterals in most of our sprawling metro area have no special provisions such as that. This is a utility rule also, not the AHJ's.

Thanks

 

[Gregg Harris]

230.8 Raceway Seal. Where a service raceway enters a building or structure from an underground distribution system, it shall be sealed in accordance with 300.5(G). Spare or unused raceways shall also be sealed. Sealants shall be identified for use with the cable insulation, shield, or other components.

300.5(G)
(G) Raceway Seals. Conduits or raceways through which moisture may contact live parts shall be sealed or plugged at either or both ends. Informational Note: Presence of hazardous gases or vapors may also necessitate sealing of underground conduits or raceways entering buildings.

 

[PetrosA]

Haven't heard that term before. Around here (Columbus) in the downtown network we install a "firebox" for laterals, a large enclosure with busbars for the utility and the premises wiring to individually connect to so no smoldering insulation can burn from a building into the underground utility ducts.

Is that like an 'end box'?

No. An endbox is usually something along the lines of a 16x16x12 box with a conduit coming in the back (sometimes with a connector, sometimes not). The POCO wires get spliced to the customer owned wiring here and feed out to a trough and meters, meter bank or a single meter. It's been a long time since I worked on one, so my memory's a little fuzzy about the details. I seem to remember some of them feeding out to a fused disconnect before they hit the meter, but that wouldn't make sense...

 

[Darr247]

While what you referenced to is correct, just placing a link like that to the code article doesn't help everyone. To use the link/site you must have a subscription. Not everyone has such a subscription. Just FYI.

FWIW... bookmark this one - http://code.necplus.org/sample/document.php?id=necss:70-2011:necs70-300.5
Substitute the section you want for 300.5; If you want a different year, substitute it for 2011.

When you click the subscribe now link on the login page at code.necplus.org, it says, "The product you requested is no longer available."

 

[GoldDigger]

FWIW... bookmark this one - http://code.necplus.org/sample/document.php?id=necss:70-2011:necs70-300.5
Substitute the section you want for 300.5; If you want a different year, substitute it for 2011.

When you click the subscribe now link on the login page at code.necplus.org, it says, "The product you requested is no longer available."

That is NFPA pulling the plug on NECPlus and forcing current and new users still on NEC cycles before 2014 to pound sand. :thumbsdown: