PVC SCH 40 underneath a concrete slab in a building

[Woodallsam]

What is the minimum cover requirement for PVC Sch 40 underneath a concrete slab inside of a building?
I am running 2" pvc for a chase for low voltage (under 50v) it is within the exterior walls but passing through one interior stem wall.
I am referring to table 300.5 ( 0-600v), minimum coverage requirements, and I am trying to understand PVC within the concrete itself. My conduit is 3-3/4" below the slab line and the inspector is asking for 4 inches minimum, which is easy enough this time, but it's got me thinking and looking at this table and I only see four inch minimum under a concrete exterior slab?

 

[Dennis Alwon]

Are you saying you are 3 3/4" below the bottom of the slab-- I assume a 4" slab. Hence you are almost 7" from the top of the slab???

If so you are good. You need to be 4" below the top of the slab.

 

[Woodallsam]

No, the top of my conduit is 3-3/4" below the top of the slab, giving me less than the 4" minimum coverage requirement. Originally it was supposed to be a 12" turn down slab ( My conduit is on top of the footing) but the slab height has changed, and therefore the depth of my conduit has also changed. Just trying to understand where exactly I fall in that table 300.5 which states 4" for my specific application.

Thanks for your help

 

[Dennis Alwon]

No, the top of my conduit is 3-3/4" below the top of the slab, giving me less than the 4" minimum coverage requirement. Originally it was supposed to be a 12" turn down slab ( My conduit is on top of the footing) but the slab height has changed, and therefore the depth of my conduit has also changed. Just trying to understand where exactly I fall in that table 300.5 which states 4" for my specific application.

Thanks for your help

Sounds like you need an extra 1/4" . I am surprised the inspector caught that

 

[Smart $]

The required cover "Under a Building" for all types is 0 inches.

 

[infinity]

Are you under the slab or in the slab?

 

[Dennis Alwon]

Are you under the slab or in the slab?

From his response he is a 1/4" into the bottom of the slab. The slab is only 3 3/4" thick instead of 4"

 

[mwm1752]

interior under building 0"

 

[Sparky2500HD]

Think about it, when job specs allow it you can run pvc in the slab itself. Pretty sure the code only states min depth for the exterior.

 

[GoldDigger]

Think about it, when job specs allow it you can run pvc in the slab itself. Pretty sure the code only states min depth for the exterior.

For interior, under the floor, you need at least two inches of concrete for a long run of service conductor. In that case it remains technically outside the building.
Ordinary feeder and branch wiring has no such limit.

 

[paul]

For interior, under the floor, you need at least two inches of concrete for a long run of service conductor. In that case it remains technically outside the building.
Ordinary feeder and branch wiring has no such limit.

OP states within interior of building for conduit with less than 50V cables.