Shared plumbing between laundry room and bathroom

jmyyz · 11-11-2009, 05:31 PM

Hi,

The house I've recently moved into has a laundry room set up next to a bathroom on the second floor. Because the house is about 100 years old, it's obvious that the water inlets and drains are retrofits but since all piping is behind walls, I can't say much else from appearance.

However, when one flushes the toilet in the washroom, you can hear the trap in the laundry room gurgle and there's an obvious pressure change when the water is running one room and then turned on in the other room. So clearly, these two rooms share the same plumbing in one form or another.

My new concern is that I just installed a new washing machine and noticed that when the toilet is flushed or the water is run in the bathroom, the water hoses into the washing machine jostle a little (even if the machine is not running) as if some water or pressure is being pulled from the hoses in order to run the toilet or bathroom sink. Is this normal? Can it damage the washing machine?

Also, while the whole house has great water pressure (including the washing machine inlets) the connected bathroom has pretty poor pressure.

Having looked at some of the other changes that the previous owners made to this house, I would imagine that the piping retrofit was a bit of a DIY hack job and I would like to correct it if possible (and assuming it's actually a problem). Is there anything you can suggest as a fix (again assuming one is needed) that would be possible for a plumbing novice like myself? If it's at all possible to fix this problem without bringing down a wall that too would be nice.

Thanks in advance for your help.

travelover · 11-11-2009, 07:44 PM

Where are the pipes run? If in a basement or crawl space, it would be pretty simple to just run a new line from the source to the bathroom. It may have some partially clogged old galvanized pipe connections to the bath. Hard to know until you can see the pipes.

The main concern with washing machines is that the hoses rot over time and can burst from excessive pressure. If they are in good shape I wouldn't worry. If old, I'd replace them.

jmyyz · 11-12-2009, 01:01 PM

Thanks for the reply. The washing machine hoses are new so that doesn't seem to be a problem.

I'm sorry to be persistent but I really don't know, is there nothing wrong with the fact that the trap in the laundry room gurgles whenever the toilet is flushed in the bathroom or the shower is running?

EDIT:With some additional reading, I think what the problem is is that using the water in the bathroom syphons of some of the water from the trap in the laundry room (did I mention that I've got a pretty bad smell coming from the drain pipe in the laundry room?). I also believe through my reading that this may be related to poor venting - either a blocked vent or improperly installed piping that did not include venting.

Does this ring true to anyone with plumbing knowledge? Is there any other information I can provide to help with the diagnosis?

If anyone does know of an appropriate fix - again preferably without having to open up the wall, please do let me know.

Thanks

Blue Jay · 11-12-2009, 05:48 PM

Sounds like a plugged or no vent on the drain line so the washer drain is acting as a vent and the water is being pulled out of the trap, hence the smell.

jmyyz · 11-12-2009, 05:53 PM

Assuming no vent, what can I do?

Assuming plugged vent, what's the best way to fix this problem?

travelover · 11-12-2009, 07:49 PM

Quote:

Originally Posted by jmyyz

Assuming no vent, what can I do?

Assuming plugged vent, what's the best way to fix this problem?

Go up on the roof and see if the vent stack exits over the toilet area. If it does, you can run a drain snake (rent it) down the stack. If there is no stack, it is a fairly big job to add one as you'll have to attach to the drain line.

You might be able to add one of these:

Auto vents and automatic home sewer vents

if your local codes allow it.

Blue Jay · 11-12-2009, 09:10 PM

Since you said this is 2nd floor I would go into the attic should not be too hard to figure out the area of bath and laundry if it is vented you would find the vent pipe coming up and out thru the roof. If no vent pipe you would need to open up the wall and install one, if pipe present then the drain snake would be the thing to try.
Good luck