NHIE - Plumbing Questions with Detailed Verified Answers

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NHIE - Plumbing Questions with
Detailed Verified Answers


Question: What are the max support intervals for piping?


Ans: Check chart...now...


Question: What are the specifics about when a shield plate should be used for
plumbing?


Ans: - When the plumbing passes through a framing member 1-1/4" or less
from the face.


- The plate is min 16g steel.


- Plate must extend 1-1/2" above and below the hole.


Question: Where necessary, protect the pipes outside the thermal envelope
from freezing; aka crawlspace, attic, outdoors.


Ans: FYI.


Question: Pipes and fittings must bear what marks?


Ans: Mfr identification and markings required by applicable standards.


Question: When is a thrust block required?

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Ans: Any drain 4" or larger with a 45 degree or greater horizontal turn.


Question: How must a pipe be buried in a utility trench?


Ans: Back-layered and tampered in place. No tractor or grader until min
12" of earth over the pipe.


Question: Who determines the trench width for burying pipe?


Ans: MFR.


Question: What is the water service?


Ans: The water pipe coming from the main that supplies the property.


Question: Water service min of what depth burried?


Ans: Min 12" and/or


Min 6" below frost line.


Question: Are water and sewer pipes ok buried together?


Ans: Yes IF the sewer pipe is NOT clay or some other material not allowed
in the house.


Question: Who determines the depth for sewer pipes?

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Ans: BO and utility.


Question: Remember, you cannot undermine footings with trenches/buried
pipes.


Ans: FYI.


Question: What is required when a pipe goes through the foundation?


Ans: Sleeves or bored holes.


Question: What must happen if a pipe is wet-set in concrete?


Ans: The pipe must be wrapped or sheathed.


Question: If copper pipe is buried, what kind of material is needed?


Ans: Min Cu Type L


Question: Can gas lines be buried under the building?


Ans: Yes, but only if conduit or listed systems protect the pipe.


Question: What is the required burial depth for gas pipes?


Ans: Min 12" below grade, 18" if external damage is likely at 12".


Question: Are plastic gas lines ok buried?

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Ans: Plastic only allowed underground outside the building.


Question: When is a tracer line required for gas pipes?


Ans: - Required when the buried line is plastic.


- Corrosion resistant wire.


- Minimum 18 AWG.


- Must surface with the gas riser pipe.


Question: What kind of insulation/wrap for buried gas pipe?


Ans: - Factory applied.


- Electrical insulation for metal pipe.


- Field wrapping ok AMI for threads and fittings.


Question: When must all piping be tested?


Ans: Before cover or concealment.


Question: What is the standard for testing plumbing?