Dripping/ticking sound while using shower

I just moved into a 4-yr old house. Interesting I noticed every time someone is talking shower on the second floor guest bath, right below it on the first floor, I could hear "dripping" or "ticking" sound. It starts at very high speed, such as gun firing. It starts to slow down after initial 15-30 sec. The sound seems to move around in the ceiling area. After shutting off the water on the second floor, the sound finally tapers off very slowly after 30-45 min.

I haven't see any water stain on the ceiling. I tried cold water, it also makes the noise. I wonder what this could be.

By the way, I tried turning on cold water faucet in master bath which is right next to this bath, I also can hear dripping sound in the same area, but it went away much faster.

Thanks.

just a guess. but it sounds like you have a pebble, piece of solider, in your pipe

moving around when the water is running.

I found one of them before..when you turn on the water it goes ..tink tink tnk..across the room

then when it reachs a spot at the end of the pipe..it rattled.

took 2 days to find and the lady was pissed off at ?

maybe thats what your is.

their is another sound that is from a ceramic washer,,more of a HUMMMMMMMMMMMMMMM that is very loud

so, have you a tink or a hum ? [metal or vibration]

The ticking could be a water line expanding and contracting against part of the wood structure.

It is drain pipe and happens both hot and cold. I had the similar situation before, but the noise went away after shutting off water valve. This time the noise hangs around for almost an hour. tick...tick...tick.... or like drip...drip...drip

shiyang100 said:

It is drain pipe and happens both hot and cold. I had the similar situation before, but the noise went away after shutting off water valve. This time the noise hangs around for almost an hour. tick...tick...tick.... or like drip...drip...drip

Click to expand...

you may have a leak,,

The issue is I do not see any water stains on the ceiling. That's why I am really struggling.

Does it happen when water is on, but nobody in the shower? It could be the shower base flexing

Thanks everyone for suggestions.

I just did another round of test:
1. Close the drain of bathtub. Turn on cold water valve. No noise.
2. Close the drain of bathtub. Turn on hot water valve. noise is back.
3. Open the drain, drain the mix of water from steps 1 and 2. Noise continues.
4. Drain cold water only. Noise presents.

Thanks.

As john said, seems like a classic example of a pipe expanding in a wood stud or joist. It can happen with water lines and drain lines.