Req's for conduit below a fire wall?

[DRWeig]

OK, this is being debated with a number of architects, engineers, and fire inspectors:

I have two occupancies that are required to be separated with 4-hour construction. Rather than go thru the debates and hassles inherent in penetrating this wall with rigid conduit (for signalling circuits), there is a proposal on the table to simply place a mess of 4" U-shaped rigid conduits that originate on one side of the 4-hour wall (about 3' above finished floor), go down below the footing that supports the wall (to a depth of about 24" from finished floor to top of conduits), and then come back up the other side. Some will be used right away but most are for future use.

Some folks say this is fine, while others say the conduits need fire stopping since they are actually penetrating the 4-hour separation even though it's below grade.

Opinions please! It would be nice if I could cite a code section that addresses this but I can't find one myself...

Thanks so much for your help!

Old Dave

 

[peebee]

I'm of the opinion you should be able to run the conduits straight through the wall above grade, with normal fire stopping around the outside of the conduit. There should be no particular requirement to seal the interior of the conduit, other than having an enclosed raceway system -- for example, make sure you provide caps over spare conduits.

To state that you can't penetrate fire-rated walls leads to truely bizarre implications; you could never get any power into or out of such a room. That just does not make any sense, the intent of the codes is not to disallow any utility service to a building.

Don't take no sh*# off your architects, let them know you're the boss when it comes to conduits.

 

[DRWeig]

Ten four, PeeBee. Thanks for your input!

Old Dave

 

[peebee]

One thing to check - are your "occupancies" considered separate adjacent buildings? If so, and you are feeding one building from the other, you would be required to provide a disconnect at the point of entry, the requirements for that are identical to the usual service entrance disconnect requirements.

 

[DRWeig]

Hi Again,

Nope, they aren't separate buildings, just separate occupancies. It's a warehouse/office deal. We actually do penetrate the wall with domestic water, fire protection water, and heating hot water, but the local fire inspectors and architects don't want to buy into the 3M methods of firestopping a conduit for electrical wires....

Oh well, I'll fight the battle!

Thanks dude!

Old Dave