You might try installing an expansion tank at the water heater location to help remedy any thermal expansion that may be causing these sounds.

If the pipe material was chosen properly, and has been correctly identified for this forum, the PVC is drain/waste/vent. What is the supply piping in this house?

"You might try installing an expansion tank at the water heater location to help remedy any thermal expansion that may be causing these sounds."

An expansion tank is not going to have any effect on the plastic piping expanding as it heats up.

It is not the water expanding as it is heated but the actual pipes.
It also occurs with metal pipes, though the expansion is much smaller.

to repeat the previous two posts, the expansion is in DWV pipes (drains) not in supply pipes, so disregard the post about an expansion tank.

Breaking the one drain run that goes snap snap and installing two offset elbows might solve the problem. This double offset will make the drain pipe zigzag a little inside the wall cavity, which is fine in terms of geometry. (We're talking about the vertical part of the drain, carrying drain water downhill in a straight line). By offsetting the expansion, you create some "give" at the midpoint in the run, and you get less snap snap noise, or none at all. The best elbows for this are 1/8 bends; they can be called 135 degree turns by DIYers.

obviously you have to open the wall and live with the dust while this improvement to the DWV is implemented. Opening the wall yourself is best because you can take the time it takes to diagnose the problem completely. With the DWV pipe exposed you will hear the snap snap noise more easily, identify the conditions that make it happen and the place where it happens.

to overkill,or to add an insurance policy, you can install two sets of offsets, one high in the wall, and one low near the floor. The price is about the same, because cost of materials is next to nothing compared to the hassle of doing all this in the first place.

HTh

Thanks all for the input. As I said my husband thinks I'm nuts so I haven't told him I've posted this. I've now run into the problem I thought I might have which is I have no idea how to answer any specifics.

Brickeyee: Thanks. The problem is it clicks even when not hot water. I'm in NC FL. Most of the year our "room temp" might be considered warmer but not always - especially in winter. But I do understand what you're saying re: pipes expanding. Does very cold water have the same effect?

Bus driver: Thanks. I have no idea what the supply piping is! I can find out.

DavidRol: Thanks. I will take that advice & am more than willing to do if it will work.

I understand it's a chore - but I'm willing to go to great lengths to fix this if it can be done - at least in the Master Bath. I have a good relationship with my contractor and he will (grudgingly) fix this. DH is quite competent so if you think this is a better DIY project I can ask him (then I'll be nuts and a nag!). I'd keep a mess/hole in the wall for weeks to get this taken care of.

But is it "normal"? Why would anyone repipe with this if you had to listen to clicking all the time? Do most do what DavidRol suggests in original installation? As I said my relationship with my contractor is good, he's a man of his word. I'm not trying to "catch" him on something I'm just curious. Thanks all. I will have to confess to DH about my post & get some answers for you.

"Does very cold water have the same effect?"

Yes it does.

The pipes contract as they are cooled and if they are tightly against framing they can cause noise.

offsets are normal in multistorey buildings. FYI.

In a two story house, the approach is "no need", except now you do have a need.

Without being there and seeing and hearing, nobody can know as much as someone who IS there. Show this to your contractor, let him do a little web searching on contractor talk web sites, and he'll get back to you within 10 days. My prediction.

At this point, the only thing about which I have confidence is that the pipes are making noise. Suppose that in this case the supply piping is CPVC (and has been misidentified in the original post). Noise from such pipes, especially the hot, is not at all unusual UNLESS the installer knows the characteristics of the material and installs accordingly.

Brickeyye: Ok I get I'm kinda screwed then. Our area has some pretty extreme temp fluctuations (20's winter, 100's summer). Uggg.

DavidRo1: Not sure what that means. We have a 1 story 80's ranch. So I'm not sure if is it normal installation or not for one story construction? Most drip noise (from Master Bath) is an addition (single story). Also, pipes are not insulated (which means extreme temp fluctuations - but that I've resigned that to PITA girl and I do need to get over - left that from OP.) Don't know if that contributes.

DH agreed with no for expansion tank - heater far from pipes & what you said about Supply v DWV. After being annoyed with me, he thought about it and said hum. Contractor tried to repair supply pipe, not DWV pipe. And DH said most def pipes are proper (for water consumption as opposed to other PVC pipes used for other applications I guess - sprinklers, etc.)

Thanks so much for advice.

"Ok I get I'm kinda screwed then. Our area has some pretty extreme temp fluctuations (20's winter, 100's summer). Uggg. "

If the pipes are in inside the thermal envelope of the house they will not see weather extremes (assuming you have heating and cooling).

Even water temperatures do not normally very as badly as the outside temperature sine the lines are buried.

The ~40 F cold water to the ~100+ F hot water are usually all you really need to be concerned with, and they are still relative to the interior temperature of the house.

You might try locating the noise closer using a mechanics stethoscope.
By touching the probe to the wall you can start to find locations where the noise is louder, then investigate getting some clearance between the pipe and framing.

Sometimes it can be as simple as slightly moving the pipe as it passes through a hole in the framing.
A pipe strap or just some padding may be all it takes.

The real hassle is locating the noise generating spots, accessing them, and then repairing the access openings.

Non-textured drywall (smooth finish) is actually pretty easy to repair.

ehgator

i'll take back anything i wrote until I see more information from you.

Web search and see images.
Then, you know what kinds of pipes look like what.
And, you will know enough to know how to remember the terms the GC will tell you.

Keywords to start with might be CTS, CPVC, PVC, ABS, Pex, iPex, copper, etc.

Take a picture of the offending pipe material.
Ask a few locals.
Look at pipes in a hardware store.
Ask the GC what pipe material you have.

Some people don't know the difference between sugar and salt in the kitchen, and then they learn. Happens when one is very young. Same thing with pipe wall materials. Happens when one is an adult.

i second what brickeyee wrote. And your pipes being uninsulated is not a problem.

identifying the pipe type you have and then spotting the place where the noise starts are the only things to do.

Hi again. I think I cross posted last night with bus driver (didn't see your post until I posted mine). Then I couldn't post twice unless I changed subject line...anyway...

Thanks and yes, I will identify the pipe type & call the GC. DH is so very annoyed with me! I think we knew what the problem was but I wanted the why - and is it normal - and can it be fixed - and am I nuts for wanting this fixed - and did the plumber screw up on installation...that sort of thing.

I def have more info to work with thanks to all your info. Thanks so much.

I have the same problem. I had my whole house repiped in Ocoee, Florida with Lewis CPVC 1109 3/4" piping and I hear noises mainly in the afternoon where the sun hits the front of our house. I think this is from the pipes expanding and contracting against the trusses. The constantly make noise when they heat up and then when you open a cold water faucet anywhere they make all kinds of racket as the cold water shrinks the piping back. There has got to be something that can be done about this and I am sure we are not the only ones with this problem. Thanks for any help you may have. Frustrated

Ronnie, a new thread for your problem may bring more responses. Are your pipes getting direct Sunlight? That is not permissible for CPVC. Next, the pipes will move as the temperature of the pipe changes- for sure, guaranteed. So the fix is to keep the pipes from contacting the framing and to make sure the pipes are free to move without rubbing anything.

We have the same issue - FL repipe with CPVC. The pipes make noise after hot water is used in the mornings...it clicks, like a dripping sound for 10 minutes after the water has stopped. This is in the summer. We had the plumber come back out and they loosened some of the straps. This provided quite a bit of improvement as the issue is only in the mornings now and not throughout the day as it was before. The issue, I think, is because the pipes travel so far. We have a one story house and the pipes are in the attic. It is the strapping, I believe, that is causing the pipes to make the "dripping" sound. It is VERY annoying to me, but it does not bother my husband (he is the one showering in the mornings while I am sleeping). The sound wakes me up. I would have gone with PEX had I known about the sound issue. The concern I have is the stress on the pipes/straps causing damage on the joints/connectors.

You can pad every strap to try and reduce the noise.

In many cases a double thickness of wax paper is all that is needed to let the pipe slip on the strap without making any sound.

Here in BC, they apparently mandate an expansion joint in drains for multi-story houses...I think to allow for the house settling. I wonder if that would work in this case, or if it would be an alternative to the offset described above?

A long time ago I chased down the clicking in a CPVC setup.

It was the pipe grabbing and then releasing on the pipe hangers and in a couple of bored holes through framing.

Wax paper lets things move without making any noise.

It even works on copper pipes.

Interesting idea, the waxed paper, haven't seen it.

I quite often put a scrap of rubber between copper pipe and the anchor/fastener.

"scrap of rubber"

Wax paper is far cheaper.

The stick-slip behavior appears to be the cause of the noise.

Right. The bits of rubber I use are free, every so often I go to a tire shop and beg an innertube that's been scrapped. Mostly, I use it to make gaskets.

If ppl would read the instructions and install the pipe correctly to begin with they wouldn't have to try to re-invent the wheel with wax paper and rubber.

Similar problem here. Maitland, FL. Repipe with PVC (CPVC?) 4 years ago. Townhouse, so 2 stories.

Now, every time water is used in the kitchen there are clicking/tapping/dripping sounds in the master bedroom - directly above kitchen. Getting worse as time passes.

Infuriating.

And worrisome.