Ridgid PVC Conduit Schedule 40, 80 or Both?

[jar546]

Am I allowed to channel into a concrete floor to run Schedule 40 PVC to a kitchen island and then grout in the 1/4" of space between the top of the conduit and concrete floor?

300.4 Protection Against Physical Damage.
Where subject to physical damage, conductors, raceways, and cables shall be protected.
(A) Cables and Raceways Through Wood Members.
(1) Bored Holes.

In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed through bored holes in joists, rafters, or wood members, holes shall be bored so that the edge of the hole is not less than 32 mm (11⁄4 in.) from the edges of the wood member. Where this distance cannot be maintained, the cable or raceway shall be protected from penetration by screws or nails by a steel plate(s) or bushing(s) at least 1.6 mm (1⁄16 in.) thick, and of appropriate length and width, installed to cover the area of the wiring.
Exception No. 1:
Steel plates shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid PVC conduit, RTRC, or electrical metallic tubing.
Exception No. 2:
A listed and marked steel plate less than 1.6 mm (1⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.

 

[e hilton]

300.4 seems to be talking about going through wood framing. You question was about a concrete trench.

 

[wwhitney]

Am I allowed to channel into a concrete floor to run Schedule 40 PVC to a kitchen island and then grout in the 1/4" of space between the top of the conduit and concrete floor?

The relevant reference is 300.4(F) "Cables and Raceways Installed In Shallow Grooves".

The Exception there also covers rigid nonmetallic conduit. As the schedule is not specified, that would cover both Schedule 40 and Schedule 80 PVC conduit. So yes, that is allowed.

Cheers, Wayne

 

[jar546]

300.4 seems to be talking about going through wood framing. You question was about a concrete trench.

I am getting to my point. First I want to see the thoughts on this.

 

[jar546]

The relevant reference is 300.4(F) "Cables and Raceways Installed In Shallow Grooves".

The Exception there also covers rigid nonmetallic conduit. As the schedule is not specified, that would cover both Schedule 40 and Schedule 80 PVC conduit. So yes, that is allowed.

Cheers, Wayne

I see your point. I also see the e-hilton's point that I was referencing a code about wood framing members and not concrete.

 

[sclavette]

How else are you going to provide the provisions required for a future island receptacle in 2023?

 

[e hilton]

How else are you going to provide the provisions required for a future island receptacle in 2023?

You rough in a proper conduit under the slab before it is poured, come straight up into a j-box in the floor under the cabinet.

 

[steveray]

(F) Cables and Raceways Installed in Shallow Grooves.



Cable- or raceway-type wiring methods installed in a groove, to be covered by wallboard, siding, paneling, carpeting, or similar finish, shall be protected by 1.6 mm (1⁄16 in.) thick steel plate, sleeve, or equivalent or by not less than 32-mm (11⁄4-in.) free space for the full length of the groove in which the cable or raceway is installed.
Exception No. 1:
Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid PVC conduit, RTRC, or electrical metallic tubing.
Exception No. 2:
A listed and marked steel plate less than 1.6 mm (1⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.

 

[jar546]

You rough in a proper conduit under the slab before it is poured, come straight up into a j-box in the floor under the cabinet.

What about channeling out an existing slab in a high-rise condo with an R2 above and below you? This is more along the line of the description I provided.

 

[Mr. Inspector]

If the PVC conduit is in a slab on grade it could be considered "under a building" in which NEC 300.50 would require it to be 4" deep when under a slab. IRC says it needs to be 0" if under a building but if under a 4" slab it needs to be 4" below.

 

[wwhitney]

If the PVC conduit is in a slab on grade it could be considered "under a building" in which NEC 300.50 would require it to be 4" deep when under a slab.

Only if carrying conductors over 1000V. For normal voltages, 300.5 applies and the requirement is 0" under a building.

Cheers, Wayne

 

[ICE]

What about channeling out an existing slab in a high-rise condo with an R2 above and below you? This is more along the line of the description I provided.

Does the channel compromise a fire rating? 1/4" of grout will not last long unless there is a solid flooring over it like tile etc.

 

[steveray]

Only if carrying conductors over 1000V. For normal voltages, 300.5 applies and the requirement is 0" under a building.

Cheers, Wayne

Except this would not be under a building, it would be embedded in the concrete floor of the building....

 

[wwhitney]

Except this would not be under a building, it would be embedded in the concrete floor of the building....

Is this spelled out anywhere in the building codes? For concrete slab on grade construction, where the lower vertical limit of the building is located exactly? It's not addressed in the NEC, to my knowledge.

Cheers, Wayne

 

[steveray]

Is this spelled out anywhere in the building codes? For concrete slab on grade construction, where the lower vertical limit of the building is located exactly? It's not addressed in the NEC, to my knowledge.

Cheers, Wayne

Exactly why the electrical needs to stay in the IRC....
For starters...

SECTION R506
CONCRETE FLOORS (ON GROUND)
R506.1 General. Concrete slab-on-ground floors shall be
designed and constructed in accordance with the provisions
of this section or ACI 332. Floors shall be a minimum 31/2
inches (89 mm) thick (for expansive soils, see Section
R403.1.8). The specified compressive strength of concrete
shall be as set forth in Section R402.2.