Gas pipe below slab

[Marc Morin]

I've only a few code cycles and was trying to determine when 1211.1.6 Piping Underground Beneath Buildings was adopted to require gas pipe below a slab be within conduit vented above grade to the exterior. Thanks.

[H.G. Watson, Sr.]

I've only a few code cycles and was trying to determine when 1211.1.6 Piping Underground Beneath Buildings was adopted to require gas pipe below a slab be within conduit vented above grade to the exterior. Thanks.


I believe you have made a typo, and meant to cite 1311.1.6 (2007) or 1312.1.6 (2010) of the California Mechanical Code.

Its helpful if you IDENTIFY (reference the source & edition) for a citation when asking a question about same (and correctly type the section/subsection number ;) ).


The reference I believe you are inquiring about is from , Chapter 13, "Fuel Gas Piping", section 1311.1.6 of the 2007 or 1312.1.6 of the 2010 California Mechanical Code (based upon IAPMO's 2006 or 2009, respectively, UMC or Uniform Mechanical Code) which borrows in its chapter 13 most significantly and verbatim from 2002 NFPA 54. "Note: Portions of this chapter have been reproduced in their entirety from NFPA 54-2002".

The 2007 California Mechanical Code, 1311.1.6 is comprised of 2002 NFPA 54:7.1.6 & 7.1.6.1 (NFPA 54 is the National Fuel Gas Code, a.k.a. ANSI A223.1), which read thusly:




1311.1.6 Piping Underground Beneath Buildings. Where the installation of gas piping underground beneath buildings is unavoidable, the piping shall be encased in an approved conduit designed to withstand the superimposed loads.{NFPA 54:7.1.6}
The conduit shall extend into a normally usable and accessible portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be sealed to prevent the possible entrance of any gas leakage. When the end sealing is of a type that will retain the full pressure of the pipe, the conduit shall be designed for the same pressure as the pipe. The conduit shall extend at least four (4) inches (100 mm) outside the building, be vented above (*) grade to the outside, and be installed so as to prevent the entrance of water and insects. {NFPA 54:7.1.6.1}


(*)2010 CMC 1312.1.6 Reads Identical to the above except insert the word: "finished" where indicated above with the red asterisk.

Why does it matter when? Noncompliance would not be a "grandfathered" condition, in Cali, regardless.

[Marc Morin]

It's not a typo (it's from the 2010 California Plumbing code).

[H.G. Watson, Sr.]

Okaaaay.Thanks for identifiying your previously unreferenced unquoted citation.It reads IDENTICALLY as I quoted from CMC above.Including its reference to NFPA 54 and the specific citations thereof (and quoted verbatim).Again, Both Parts 4 & 5 of California's Title 24 are published by the SAME organization! Both the California Mechanical Code based on Uniform Mechanical Code, and the California Plumbing Code based on Uniform Plumbing Code, are published by IAPMO; Applicable Chapters of same, entitled Fuel Gas Piping and Fuel Piping, respectively, reference the SAME citations from NFPA 54, and quote same verbatim.And...again: WHAT is the purpose, the point of, the reason for your question, in the first place???Noncompliance is an unacceptable, defective, dangerous & hazardous condition, regardless!

[Marc Morin]

I'm not questioning it's intent but it origin. Someone will pop up who recalls when this requirement first appeared (likely within the first few years of slab foundations--but maybe much later). I see it on homes 10-12 years old, but not much older.

[Jerry Peck]

I can't tell you about California - I'm sure West Coast Jerry can - but that has been in the codes for a very long time, much longer than the 10-12 years you are wondering about.

[Marc Morin]

Thanks Jerry...yeah, I would imagine it's at least 30-40 years old, but I've never seen that set-up on slab homes with original island cooktops from the 1970's...this might not be a 'known' given the multiple jurisdictions, over-lapping plumbing/fuel/mechanical requirements, etc.

[Rod Butler]

I can recall the requirement back when I started in the design business, over 35 years ago. Sorry I can't be more specific as to the code reference.

[Marc Morin]

Thanks Rod. Do you recall if the spec's required were somewhat similar to the attached graphic?