I'd like to put a 10" or 12" shower arm on a shower I built. The arm is secured by a drop eared ell that is screwed to 2x4 blocking. The arm will hold a standard shower head.

Is this okay or do the longer arms need a special attachment behind the wall?

I don't think you would need any special support, open the link below and it shows some of the 12” arms, Thanks.

John


12" long shower arm - Google Product Search

Agree with afaroo, you should be fine using existing drop eared ell.