plumbingshower
I'm nearing completion of a bathroom remodel and just need to install the fixtures. I have not had to install a brand new shower head before and am unsure of what I need to complete this project.
The pipe for the shower head is recessed into the wall, about flush with the inside of the wall.
What do I need in order to extend this pipe so I can attach my shower head? Thank you
This is a picture of one example of a rough shower plumbing install:
As you can see, at the top there is a cross brace, and there is a 90 degree angle that's been mounted into that brace secured, preferably with screws but possibly with nails.
My guess? Your shower head was braced with nails, some idiot hit your shower head pipe pretty hard and pulled the nails loose, and the sound you heard was one of the nails falling out.
It's not serious - as long as you don't put any weight on the shower head - and the fix will involve opening up the walls. Technically you can fix it from behind, so you won't have to destroy tile in the process, but that's a harder way to do it. Basically you have to pull the wall behind the shower, cut the pipe to the shower head, pull the brace, re-secure the shower head, replace the brace, and then fix the feed to the shower head w/ a connector.
For copper pipe, hot (~50 C) water should only flow at approx 5 ft/second. Flow of less than one or two ft/sec can also be a problem. Based on the diameter of the pipe (1/2 in type L), 0.72 gpm flows at 1.0 ft/second, so this would suggest a maximum of 3.6 gpm for the pipe (assuming 5 ft/second). Also, you must worry about the pressure drop. Use table 6 of The copper Handbook, at 5 gpm, the pressure loss is 0.161 psi/ft. Assuming your supply is 50 psi, and you need 35 psi to be delivered to the shower head, you can have a maximum pipe length of (50-35)/.161=93 ft. Figure 7 shows how fittings should be counted due to their larger pressure drop. A 90 degree fitting counts as one foot. Additionally, water pressure will decrease with elevation by approximately 0.433 psi/foot.
As long as you meet these two restrictions, you're fine. Since you need 4.5 gpm, and your pipe is likely less than 93 feet, things should work fine.
Best Answer
You need to install a shower arm.
One end will (should) thread into the pipe in the wall, and the shower head will thread on to the other end.
Don't forget to use pipe dope/tape on the threads.