Conduit on a roof?

[mbsi]

I need to run a feeder (2" with 3-3/0,1-1/0,#6gnd)in conduit on a roof of a building. Can I use EMT with rain tight fittings or would this be a "severe physical damage" location (This is a strip mall with a flat roof). I thought I read that IMC or RMC had to be used but I can't find the reference.

Thanks for the help

 

[hbiss]

Re: Conduit on a roof?

I don't think you will find anything prohibiting EMT. I wouldn't use it though just because I've seen too much of it rusted through, not necessarily damaged.

Incidentally, whatever conduit you use should be run on blocks or some other support to keep it up off the surface.

-Hal

 

[hurk27]

Re: Conduit on a roof?

severe physical damage would be determined by your AHJ. But it should be based upon the normal use of the area that the equipment will be installed in. Roof tops should not be subject to severe physical damage unless you are having planes land on it?

Hey that would a good definition to add to the 2008

 

[jtester]

Re: Conduit on a roof?

I don't think that "severe physical damage" will be an issue. Can you find listed raintight 2" EMT fittings? I thought UL dropped raintight listings about 2 years ago, and only a few manufacturers can comply with the new standard, and that is generally limited to about 1".

New Mexico threatens to enforce the new listing requirements but they have ignored the problem so far.