Why Can T You Use Pex For Tub Spout Drop

Original poster 4 points 3 years ago.

Why can t you use pex for tub spout drop.

If you use pex for the tub spout when you turn on the water to the tub water will back up through the shower head due to the reduced inner diameter of the pex it s called stacking. You can connect a compression type shutoff valve to the one half inch copper stub out and then connect your fixture. Copper would help give more support to the drop ear fitting and tub spout which is probably why they recommend it. How did this project turn out.

Use a drop ear bend support to hold the tubing in a tight bend right. Why can t you use pex for a tub spout. 2 reasons i learned. Copper is the only professional installation material.

The interior diameter of pex is actually a fraction smaller than copper this forces water to come out of the shower at the same time as the tub spout. I m certain they do not want you to use pex from the drop ear to the tub spot but you could probably use it between the faucet and drop ear. In areas that are concealed like under a kitchen sink or vanity cabinet you can eliminate a joint by running pex supply directly to the shutoff valve. Also a lot of tub spouts have installation methods that only work with copper stub outs.