I am installing a new bathroom in my attic. I just finished the demo today, and have a very interesting drain/vent stack. I was previously planning on running a new stack down to tie it into the second floor below the 2nd floor fixtures, but when I saw these stacks it makes me think that the attic was previously prepared for plumbing. There are also 2 capped off copper lines which strengthens my assumption.

I am wondering if someone can take a look at this picture and tell me what the best plan of action is. I do have some preliminary drawings, but first I need to know where I can tie the new plumbing into. I would greatly appreciate any help. Thanks.

Hi Zaothusia...

Looks like you have a pair of water pipes already run up there... that's certainly a bonus!

In terms of the waste line, you need to open the floor up a bit so we can see if they left a sanitary tee off for the future bathroom as well..?

The fitting above the floor will probably not help you in this case unless you are planning on building the bathroom up off the floor whatever height the top of the cast iron hub of the fitting is off the floor or maybe you could install a backflush toilet... hmmm? What does the pipe measure off the finish floor to center of the larger copper pipe/cap?

It certainly looks like there was a bathroom there previously... but that doesn't mean it is piped by code. For example, they may have added this bathroom to a VENT STACK which means that the toilet below may not be considered vented anymore and that is not acceptable plumbing practice.

You may need to open wall downstairs to determine if the toilet is wet vented from the floor or from the waste stack...

For now, open the attic floor up a bit so that we can see if there is a fitting below the floor... this fitting, if present, will be the fitting you will connect into for your bathroom (as long as bathroom downstairs is vented correctly)... at least if you want toilet to sit on floor... ;)

Finally, you may need to connect into waste stack below 2nd floor fixtures... but let's hope not!

Let us know...

MARK

Unfortunately there is not a fitting below the floor, no idea why they would put the fitting so high. What I am hoping is that I can cut the pipe right beneath the floor and put in a pvc t with some mission clamps. I have done this before and it would minimize my patching, I would only need to frame a little square in my second floor bathroom.

Will I be able to tie in my vents to the smaller stack on the left hand side? I am not sure how the 2nd story bathroom is vented and there is no access panel.


Sorry no new picture, my wife took the camera. You can't see it very well anyway, I had to stand directly above it with a flash light.