Pool heater - natural gas pipe buried only 9 inches deep

[HelenInCA]

Hi everyone!

I'm currently in the process of building a new gunite pool and it is getting close to the finish stage. Currently we are in the process of finishing the concrete pool deck.

However today I did discover something concerning. We are going to have a gas heater for the pool, so the pool builder installed a yellow plastic natural gas pipe running from the front yard gas meter to the backyard of the house. I was present during most of the time when they were installing the gas pipe and it looks like the line was buried 16-20 inches or so underground.

But there is one area along the path of the gas line where the dirt is very narrow - between the concrete walkway and the retaining wall and in this area the workers only buried the natural gas line about 9 inches below the top of the concrete. I have attached the picture.

At this point, the gas line is already fully connected to the equipment and gas meter outside and most of it is already buried. I read online that the gas line should be buried 18 inches underground for safety. I brought this up to my builder and he just said he'll cover that area with more concrete or something and then it'll be fine.

Since its gas I still have some concerns. Do folks here think what the builder is suggesting is acceptable? Are there any increased risks with the gas line being only 9 inches deep? Or should I be demanding that they dig it up and redo it at the proper depth?

Thank you!

 

[sande005]

I'd call my local building code official and ask. In my town, they try to make it out the same day if there is a suspected code violation. He may accept the builders suggestion, or may require him to bury it deeper.

 

[proavia]

Welcome to TFP!

My question is why didn't the building inspector already inspect the gas line install, before any of it was buried?
What else on your pool build was not inspected by the city inspector?

Most building permits have areas for the building inspector to sign off as the build progresses.
Rebar (pre gunite), plumbing, electrical, gas, pre plaster, barrier, etc.

 

[JoyfulNoise]

From the San Jose Building Code -

https://www.sanjoseca.gov/home/showpublisheddocument/94721

Looks like 12” is the minimum unless the area wil experience significant forces in which case it would be 18”. Depends on how they define the word “cover” but in my experience that means soil/fill cover excluding any flatwork above that. You can ask an inspector what their official definition is.

 

[Skelly_GSR]

I don’t see a tracer wire either.

 

[JamesW]

Less than 12" might be acceptable if the pipe is in conduit or shielded.

It depends on if your local inspector allows this and if they require 12" whenever possible.



1210.1.1 Cover Requirements
Underground piping systems shall be installed with a minimum of 12 inches (305 mm) of cover.

The minimum cover shall be increased to 18 inches (457 mm) if external damage to the pipe or tubing from external forces is likely to result.

Where a minimum of 12 inches (305 mm) of cover cannot be provided, the pipe shall be installed in conduit or bridged (shielded). [NFPA 54:7.1.2.1 — 7.1.2.1(B)]

Piping Underground | UpCodes

Explore a searchable database of US construction and building code. Code regulations are consolidated by state and city for easier navigation.

up.codes

 

[JoyfulNoise]

I don’t see a tracer wire either.

I don’t see a requirement for that in the code [see Post #9] but I also agree that it is good practice to have tracer wire wrapped around a gas line in case future ground work is necessary. Good catch.

 

[JoyfulNoise]

Less than 12" might be acceptable if the pipe is in conduit or shielded.

It depends on if your local inspector allows this and if they require 12" whenever possible.

View attachment 615542

1210.1.1 Cover Requirements
Underground piping systems shall be installed with a minimum of 12 inches (305 mm) of cover.

The minimum cover shall be increased to 18 inches (457 mm) if external damage to the pipe or tubing from external forces is likely to result.

Where a minimum of 12 inches (305 mm) of cover cannot be provided, the pipe shall be installed in conduit or bridged (shielded). [NFPA 54:7.1.2.1 — 7.1.2.1(B)]

Perhaps the inspector considered the eventual installation of an overlying concrete deck to be the sufficient protection against damage

 

[JamesW]

7.1.7.3 Tracer Wire.

An electrically continuous corrosion resistant tracer shall be buried with the plastic pipe to facilitate locating.

7.1.7.3.1 The tracer shall be one of the following: (1) A product specifically designed for that purpose (2) Insulated copper conductor not less than 14 AWG

7.1.7.3.2 Where tracer wire is used, access shall be provided from aboveground or one end of the tracer wire or tape shall be brought aboveground at a building wall or riser.


1210.1.7.2 Tracer Wire
An electrically continuous corrosion-resistant tracer shall be buried with the plastic pipe to facilitate locating. The tracer shall be one of the following:
A product specifically designed for that purpose.
Insulated copper conductor not less than 14 AWG.
Where tracer wire is used, access shall be provided from aboveground, or one end of the tracer wire or tape shall be brought aboveground at a building wall or riser. [NFPA 54:7.1.7.3 — 7.1.7.3.2]

https://www.sanjoseca.gov/home/showpublisheddocument/94721

 

[JamesW]

I don’t see a requirement for that in the code

Pages 109 and 110.

 

[Newdude]

Perhaps the inspector considered the eventual installation of an overlying concrete deck to be the sufficient protection against damage

Depending on how he felt that day, it may be '12 inches down'. My guy was hardcore on team 'patio depth doesn't count'.

@HelenInCA you know exactly where it is, and about how deep it is. If you were ever to be digging along it's path it wouldn't be best practice to dig with a machine whether it's at 9 inches or 18. It should only be exposed gently by hand tools if necessary. When i was burying these we also laid a strip of yellow caution tape a few inches above it as further protection. I don't see a practical reason it needs to be 12 to 18 inches here when in the end it'll be 12 inches more or less. If you sell the house, advise the next owner and give them the pics for when they replace the patio/ walkway.

You have pics of it dead on in place, but evenso should call 811 if the need ever arises to mark it out before digging along it's path. (Also where the tracer wire comes in handy)

 

[JamesW]

The Inspector needs to approve of the installation before covering.



Was an inspection done and did it pass?

Either way, the inspector needs to review and determine what needs to be done.

The gas line needs to be permitted to a licensed gas contractor.

Most likely, the gas and electrical parts of the job were subcontracted out to licensed contractors in those trades.

Have you talked to the licensed gas contractor listed on the permit?

You can contact the city and get copies of all permits and inspections issued and completed for your property.