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A.D. Miller
04-27-2009, 07:30 AM
I see that Carlon ENT, d.b.a. "Smurf Tubing", is approved for concrete encasement. How does this square with the IRC requirement for Schedule 40 PVC in concrete foundation penetrations?

A.D. Miller
04-27-2009, 08:17 AM
Now I know, from past experience, that there are numerous sparkies on this forum who would at tleast profess to know an answer to this question. Please be so kind as to share that information with me some time today.

Thank you sooooo very much!:D

Jerry Peck
04-27-2009, 09:41 AM
I see that Carlon ENT, d.b.a. "Smurf Tubing", is approved for concrete encasement. How does this square with the IRC requirement for Schedule 40 PVC in concrete foundation penetrations?

Aaron,

Because you are talking about two different things.

ENT (electrical non-metallic tubing, or "smurf tube") is allowed to be "encased in" concrete, such as when used in concrete slabs (or foundation walls) and run from one location/box to another location/box prior to concrete placement, then when the concrete is placed, those runs become "encased in concrete" only leaving the concrete where it exits at each location/box.

Your comparison is to a "penetration through" concrete, such as where a raceway such as RNC (rigid non-metallic conduit, or your typical Sch 40 or Sch 80 PVC) penetrates through a foundation wall from outside to inside.

The smurf tube will need to be back from the surface 1-1/4" minimum to provide the proper clearance from the nailing surface (the entire area can be classified as a nailing surface) and 1-1/2" back to meet AC 318 requirements for minimum concrete cover for piping, conduits, etc.

A.D. Miller
04-27-2009, 10:13 AM
Aaron,

Because you are talking about two different things.

ENT (electrical non-metallic tubing, or "smurf tube") is allowed to be "encased in" concrete, such as when used in concrete slabs (or foundation walls) and run from one location/box to another location/box prior to concrete placement, then when the concrete is placed, those runs become "encased in concrete" only leaving the concrete where it exits at each location/box.

Your comparison is to a "penetration through" concrete, such as where a raceway such as RNC (rigid non-metallic conduit, or your typical Sch 40 or Sch 80 PVC) penetrates through a foundation wall from outside to inside.

The smurf tube will need to be back from the surface 1-1/4" minimum to provide the proper clearance from the nailing surface (the entire area can be classified as a nailing surface) and 1-1/2" back to meet AC 318 requirements for minimum concrete cover for piping, conduits, etc.

JP: Thanks. On a similar note there is an AHJ in my area that does not allow ENT at Ufer penetrations. Why would that be?

Jerry Peck
04-27-2009, 10:23 AM
JP: Thanks. On a similar note there is an AHJ in my area that does not allow ENT at Ufer penetrations. Why would that be?

I am now confused: Why would you need anything to sleeve where the concrete encased electrode conductor exits the concrete encased electrode?

Or are you seeing where they take the concrete encased electrode conductor up from the footing steel, through un-filled hollow masonry units, then turn it out through the face of the unfilled hollow masonry units?

If so, it is not designed for that, however, is the hollow masonry units were filled, why would you need, or even want, to sleeve the concrete encased electrode conductor?

I'm not quite following what you are saying.

A.D. Miller
04-27-2009, 02:15 PM
I am now confused

JP: Finally!




Why would you need anything to sleeve where the concrete encased electrode conductor exits the concrete encased electrode?


JP: I did not say it was needed, but they do it.




Or are you seeing where they take the concrete encased electrode conductor up from the footing steel, through un-filled hollow masonry units, then turn it out through the face of the unfilled hollow masonry units?


No hollow masonry down here.

I'll take a picture on the next one and revisit this issue with you.