New construction upstairs shower drips after using downstairs shower

[Autotech]

I am at the tail end of finishing a new construction apartment built into a pole barn. Everything regarding the apartment is new, the barn which was built in 2005 had nothing when we started, just an open space.
The apartment has 1 bedroom downstairs, I bathroom, and a foyer. Everything else is upstairs, including the kitchen, second bathroom/bedroom and washer dryer.
It is about 90% finished, trim work, painting, and tiling upstairs bathroom still left to do.

I have a contractor who is a family friend ( he is a licensed contractor) who has been doing, or subbing out most of the work, but I do grunt work on weekends and some evenings. I started staying there on week nights to try to finish off the small stuff. So I just started using everything.

I am using the downstairs shower in the morning, and I have noticed when I come back up to get dressed the upstairs shower is dripping, or dribbling out water from the neck. No shower head installed yet, the handle isn't on it either since the tiling isn't finished.

It is very consistent in doing this, and I haven't seen it doing it other times. Not sure how long it drips since I leave for work soon after. I leave around 4:30 and the contractor doesn't get there til after 6am, he says it is never dripping when he gets in.

I heard it start once, it made kind of a short whoosh noise, then started dripping.

He says it's nothing to worry about, and is probably just because the control handle isn't mounted and it is tough to get it exactly in the middle to close it off with no handle. I have tried using pliers to get the shaft exactly closed, but I haven't mounted the handle to be positive, since they are still tiling.

His explanation seems off to me. Especially once I heard that whoosh noise.

Any suggestions or advise would be greatly appreciated.

 

[Terry]

Very strange. What shower control are you using?

 

[Sponsor]

 

[Autotech]

Very strange. What shower control are you using?

I'm not sure what specifics you looking for, the brand is moen, and it's just got one knob. I'm going there tonight so I can get more info if you tell me what your looking for.

 

[Dj2]

Did you use any water upstairs before you took a shower downstairs? Some shower heads drip a bit, hours after they were used, and then the dripping stops.

Also: Find out how the plumber plumbed the shower.

Meantime try this: Install the handle and turn it to off position. You can do that even it the tile work is not completed.
Now run the water downstairs...is it dripping upstairs?

 

[Autotech]

When I notice it dripping, I haven't used water upstairs. Although that doesn't mean using the water elsewhere might not cause it to start dripping. Last night I did run the washing machine, which is upstairs and the shower did not start dripping then.

When you say how was it plumbed, I am not sure what that means. I can tell you, the whole apartment is plumbed with pex tubing. He did not "home run" all the piping back to the utility room with the pump, pressure tank etc. At some point I did ask him if he was going to do that, and he said he could but it would use a ton more tubing and he said it wouldn't make any difference in the way the water system operated for me. This is just going to be a weekend place, so I figured no reason to spend all the extra money for that.

The shower upstairs, has the 2 lines going into the valve one on the right side and one on the left, 3 o'clock and 9 o'clock, with the pipe to the shower nozzle coming out of the top.

One slight difference, is because of the layout of the bathroom, the shower stall is 3x4 foot, but you will have to enter from the end, with the shower head on the opposite wall. So I was concerned about having to fully step into the shower to turn on the water and getting a blast of cold water, so I asked him to put the control on the side wall mid way to the entrance so you can reach in with your arm and turn on the water to let it heat up.

Hope this is the info you were looking for.

Btw this morning I paid more attention, I took my shower downstairs, after the shower, I spent probably 2-3 minutes more combing my hair, etc before walking back upstairs. It was a minute or so more before I heard the upstairs shower start dripping then turn into more of a full dribble of water. That lasted for about 2-3 minutes gradually tapering off and stopping about 2 or 3 minutes later. So it dripped or dribbled water for over 5 minutes but took a few minutes after I turned off the shower downstairs to begin dripping. Over all I would estimate it dripped enough water to fill a regular sized coffee cup. But that's totally on off hand guess. I have just been sliding the water bucket the tiling guy left there which is already partly full of water.

 

[Reach4]

I would put a pressure gauge on my plumbing, and watch the pressure after a downstairs shower.

I would go for one with a "lazy hand" (tattletale) that records the peak pressure. The pressure should probably stay under 100 psi. If not, you need a thermal expansion tank. The lazy hand can sometimes displace due to vibration. Another thing you can do is to make a video of the pressure gauge in the several minutes following a hot shower. A garden hose pressure gauge can be put on an outside hose spigot, a laundry connection, or the drain on the WH.

I wouldn't think that a shower valve would be the thing that would leak in the face of high pressure, but something very unusual is happening in your new apartment.

 

[Dj2]

"When you say how was it plumbed, I am not sure what that means. I can tell you, the whole apartment is plumbed with pex tubing. He did not "homerun" all the piping back to the utility room with the pump, pressure tank etc."

This could be your problem. Find out from your bldg dept/office if a homerun is necessary for each fixture.

I only work with copper, but if I had to do PEX, I would run a separate pipe from the manifold/hub to each fixture, regardless the amount of pipes I end up with.

 

[Jadnashua]

The seals could have been damaged when installing the cartridge, especially if the lines were not flushed prior to putting it in. On some of those, there may be two places where it will shut off, but only one of them has a fairly wide space so centering isn't super critical. Until the handle and trim are installed, the cartridge can be spun 360-degrees...you might try rotating it 180 or so, or until it turns off again (it may or may not work, but won't hurt to try) and see if that helps. The stop may not work until it is all installed.

 

[FullySprinklered]

I think you've jumped the fence and the bull ain't chasing you yet. Once everything's in place it'll probably be fine.
I've noticed in the last two houses I've lived in/owned, that the upstairs fixtures act funny because they're seldom used and there's a little spurt of air when I use them for whatever reason. Pressure issues are funny and it's not something that I have a grip on or totally understand. However, there's plenty of engineers on the site that may have better information for you.

 

[Autotech]

So I checked the water pressure as one of you suggested. It took a few days because I am not out there every night and I had to find and order the gauge. Not sure these numbers are very specific, because the gauge seems kind of cheap honestly.
Resting , no water running in the house, it was at 40 psi. The tattle tail needle showed a high of 60 psi after the shower ran.
This was checked at an outside faucet that just happens to be near the downstairs bathroom.

I'll try turning the valve around, I still haven't tried installing the handle to make sure it is at the absolute dead center close point. But if it could be 180 out, that would make sense for it being that sensitive to exact positioning.

Unfortunately at this point because of the holiday and other commitments I won't be able to try out any more of your suggestions until this weekend, because I won't be going out there in the evenings this week.

 

[Reach4]

Resting , no water running in the house, it was at 40 psi. The tattle tail needle showed a high of 60 psi after the shower ran.

Did that monitoring interval include an hour after the hot shower and no water had been used since the shower? The humidifier or the ice maker should not have used water. Did the upstairs shower drip during that interval?

If the dripping coincides with the higher pressure, that is interesting. A shower valve should certainly not leak at pressures under 150, but something seems to make your upstairs shower dribble at times. What is left besides pressure? Vibration? That seems more improbable.

 

[Autotech]

The upstairs shower dripped as is normally does now, after I finished showering downstairs. No humidifier, there is an ice maker in the fridge, but I doubt it ran or has run for awhile. The ice box is full since we first turned it on, and no one has been using the ice. So I don't think it is still making ice.

I didn't check the gauge right before my shower to see if the pressure had spiked to 60 during the night. I put the gauge on the night before. I checked it after my shower, might not have been a full hour later, but it was over 30 minutes later, and after the upstairs had stopped dripping, by that time the reading was back to 40 or so.

I haven't hear the pipes or any other plumbing make noise so far and the plumbing is all pex pipe as far as I can tell. Would pex transmit a vibration though its pipe like that? Seems like it wouldn't.

 

[Jadnashua]

40 psi is on the low side of normal. There can be pressure variations between day/night as the utility tries to refill storage towers when few people are using water. IF the spike was thermal, it typically would go much higher.

 

[FullySprinklered]

My second job tomorrow will be a mystery leak that happens upstairs after the basement shower is used. If the basement plumbing is pumped, that might be a clue; but I won't know til I check it out.