2" emt expansion rough estimate

[shortcircuit2]

I did not say that... :blink:

Steel raceways do not change 4" in 100'. Only ~1-5/8" for 100 degree swing at 40% of PVC. And then you can subtract the expansion of the structure to which it is attached (which you can also do for PVC, though Code does not mention this).

In reading the article, they say with 100 degree temp swing, you would have a 1/4 inch expansion every 6ft for PVC, every 16ft for aluminum, and every 32ft for steel.

So there appears to be an error in the diagram. Those numbers would apply to PVC...

I'll shoot the author an email.

 

[kwired]

In reading the article, they say with 100 degree temp swing, you would have a 1/4 inch expansion every 6ft for PVC, every 16ft for aluminum, and every 32ft for steel.

So there appears to be an error in the diagram. Those numbers would apply to PVC...

I'll shoot the author an email.

That is what I first thought when I looked at it, sounds more like the expected expansion out of a PVC raceway than a steel raceway, I have done many long runs that if they moved that much would have suffered some damage because I never used any expansion fittings. But I have seen much shorter runs of PVC damaged all the time from no expansions fittings.