Water piping below slab 1

[FireFreak08]

Is there a code that states you cannot run water piping (Domestic or Fire) below a new building slab? I have a unique project where at the last minute, the city decided to change where the service could connect to the city main and it basically forced a design to run below the slab for about 50 feet and then turn up into a mechanical room. I was not able to find a code saying you cannot do this, although it's not the best practice to do. Our hands were tied unless the building were to be redesigned which at that stage was not feasible.

Now the contractor is spreading word that it's "illegal" and everyone is freaking out.

 

[CarlB]

I've seen that done in several projects, and was no problem with codes or permitting that we were aware of. Sometimes the fire riser room is not on an outside wall. I've also seen a fire line pass under a building to serve that building, and other buildings. Now that might be illegal.

 

[cvg]

it is done all the time, but I suppose there is some region of the world where it might be illegal. Perhaps check the local building code

 

[EnergyMix]

If the contractor is saying it's illegal, then have them show you the code specifying where it can't be done. Tell them basically it's a case of "put up or shut up." Of course, it really helps to ask the city first about the local building code to make sure you're ok. Also many times you can find the building codes online with some diligent searching.

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[dicksewerrat]

Call the local plumbing inspector and fire marshal to the jobsite. Should take about 5 minutes for them to tell yes or no.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[FireFreak08]

Thanks everyone. Our response was basically show us the code or give us written directive from the AHJ to make a change. Plans have already been reviewed/permitted by the AHJ. So now we wait and see. I looked high and low to find a code section but was not able to.

 

[racookpe1978]

Well, in my mother-in-law's house - as in many in Texas houses at the time - the hot and cold copper water pipes WERE run through the slab-on-grade up to the fittings and sinks and appliances. They ended up needing to replace and rerun pipes when the copper eroded/rusted through and water was coming up through the living room rug before it got to the kitchen.

Expensive repairs and lots of damage. But it wasn't "illegal" per code.

Consider the dollars to run the water supply pipes through an "outside" larger conduit or "duct" under the concrete (even if that outside pipe were plastic) so the original steel/iron pipes can be replaced if a problem develops, and leakage is seen if any develops in a fire pipe. Pull the bad (or corroded) pipe, put a new one in, reconnect new pipe to good appliance or to supply pipe at the street.

 

[rconner]

I don't know exactly what you mean by  "building slab", but depending on what you are dealing with I would think there could conceivably be all manner of "codes" that at least touch on such. While I also don't know your locale nor exact intended services, examples are NFPA standards 13 and 24 relating to various fire protection etc. I believe at least recent versions of both these standards included language to the effect, "Pipe shall not be run under buildings."  However, I believe both these standards immediately followed this requirement up in the immediately following section with language to effect, "Where pipe must be run under buildings, special precautions shall be taken, including the following..."

I also don't know exactly what the OP reference to "illegal" meant , and I am not a lawyer, but I have heard that various codes or standards, or language therefrom etc. have occasionally been written/pulled into some jurisdictional regulations and even laws. In this same regard, I have no idea exactly how regulators or legal entities would regard the juxtaposition of the specific language in the two quoted sections (that are about as clear as mud to me). One would think however the intent at the every least was some care shall be taken to avoid this practice, at least under "building" slabs, but where this "must" be done one shall take at least the multiple precautions directed therein. While I didn't happen to see the following listed, they also make some sense to me in such cases:

1. Use good design, pipe and installation practices.
2. Where possible put at least some kind of safe and at least diagnostic test on the piping installation before the slab is poured.