Thank you for looking!

Ok so I've begun construction on a washer/dryer (stackable) retrofit and I need some more guidance from the experts. So far, I've opened a pantry up and run hot and cold water lines to the area. I've also added a washer box with standpipe in the pantry.

All studs I will talk about here are load bearing exterior wall studs.

The goal is/was to run the drainpipe past the dishwasher on the outside of the wall (the pipe would be exposed but we would avoid boring through the studs). Ultimately, after passing the dishwasher, I would join the washer drain to the kitchen sink with a wye. I would add 2 AAV's (1 post kitchen trap and 1 post washer trap, if anyone is curious).


Turns out, the dishwasher depth prohibits the pipe from being run behind it. I had initially thought it would work since there are hot and cold lines running behind it. I thought wrong.

Now to get passed the dishwasher, I could bore 2" holes through the exterior studs, or notch them 1.5" and remove the drywall for 2" passing. I know that doesn't meet code. I am troubled because a neighbor of mine paid a contractor to do the work and was successful.

I looked at his house (these are identical townhomes) and he had no visible washer drain pipe. I literally have no idea where they would have put it, unless they bored through all of his exterior studs. He mentioned that they did remove the dishwasher but never did any work under the sink.

Any initial thoughts? I really appreciate the help.

Here are some images:

http://i1093.photobucket.com/albums/i421/smogowski/schematic.jpg

http://i1093.photobucket.com/albums/i421/smogowski/problem1.jpg


http://i1093.photobucket.com/albums/i421/smogowski/DSCN0183.jpg

http://i1093.photobucket.com/albums/i421/smogowski/problem1-2.jpg

More size appropriate image.

HI Stephen...

If there is no way to get under the floor then the only other way will be to drill out the exterior studs. Drilling is the preferred method as it will leave some strength to the studs, at least compared to notching them, OK?

I know these are exterior wall studs, but it is an accepted practice to drill through these for drain/vent pipes... notching is the no-no!

Finally, check the dishwasher space at the back of the dishwasher... may be able to fit a pipe here if you lower the drain pipe a little lower than you have it now. If that doesn't work then drill the holes and connect as needed.

If you can connect into the drain pipe inside the wall that may eliminate the need for the sink AAV if you can connect below the kitchen sink drain connection... ;)

Back to you...

Mark

Thanks for the response. The exterior studs are not 2x6- they are 2x4 and with a 2 1/8" hole in the middle it is going to significantly weaken the frame. I also would have to drill through multiple studs and all my research tells me this is a bad idea.

A huge problem that hasn't been addressed is the fact that to drill through the studs would require removing all the cabinets (huge job).

As I mentioned, a similar home was remodeled and they never tied into the sink. I'm thinking they went outside with the PVC.

Ever heard of laundry to landscape irrigation using graywater? Yes, I'm desperate but I'm considering everything.

Actually, I assumed that the wall was a 2"x4" wall, and believe it or not, it is an accepted practice to drill 2-9/16" hole in these studs to do what you are doing...including drilling through multiple studs. See, here, the walls are perfectly fine as the exterior sheathing, sheetrock, and all the other studs are locked into place and drilling 3-6 or more of them will not weaken the wall in any way that will create issues for you. I have been doing this for over 30 years in a number of different states and have never had a building or plumbing inspector have an issue...I promise, or I wouldn't have suggested it...;)

What I don't understand is the need to "remove all cabinets"? Why? You should just have to remove the sheetrock in behind the dishwasher and drill through the studs....stubbing into the cabinet base and then run the pipe exposed under the remaining cabinet(s) to connect into the kitchen sink drain as we discussed at another thread, right?

Now, I also understand that your neighbor had his washer hooked up without any major issues, but maybe it was because the kitchen sink drain was further away from the sink...closer to the washing machine or whatever it was, right? I see no other alternative for you...besides a DRYWELL, maybe?

Here, if local codes permit it, you could dig out a large drywell and fill it with concrete blocks, then 3/4" gravel, and then stub the drain pipe into the pit, cover with a weed cover, and then backfill with earth and seed for grass, etc...

Google drywell for more info.

Finally, some people do use the laundry as an irrigation, but codes usually frown on this... most of the time.

Back to you...

Mark

Thank you, Mark- you're help through this whole process has been amazing.

I am going to go for it, drilling through the 2x4 studs. Any last words of advice? It ought to be fun adding the slope in the wall and attaching the pipe. I'm going to invest in a right angle drill and hole saw right now.

Also- currently my kitchen sink is trapped and goes into the wall to a vent pipe. Since I will be venting the washer machine drain with an AAV do you think I need to add an AAV to the kitchen sink also? After all, I will be attaching it to the kitchen drain post trap.

Thanks!

Yes, but by adding the washing machine drain "post kitchen sink trap" you can suck the kitchen sink PTRAP of its water... a definite no-no... ;) Add the AAV for the kitchen sink and add an AAV for the washing machine.

So your drilling will be easier, purchase a 2-9/16" self-feeding drill bit... much faster/easier than a hole saw, but do be careful as these babies can really bite into the wood and will twist the drill hard if you don't lock the drill against the wall in the direction it will go if the drill siezes (you'll see what I mean).

Also, you can use a 2 foot level to lay out the holes on the face of the studs/cabinet walls and then transfer those marks to the drilling face of the stud using a torpedo level... very accurate for this job!

Keep me posted on progress!

Mark

Mark- I really thank you for all your help on this. The amount of work involved in this project for a plumbing novice (this was my first time even joining pipe together) was staggering. I have spent three full days on this, tackling obstacles 1 by 1.

I did everything you said, step by step, and just joined the last piece of PVC. I'll need to buy a hose to test the system- but I'm confident it's done right. Definitely put enough PVC cement to keep those joints together...

Once I finally test it, I will let you know how it went!!

THANKS AGAIN, I TRULY APPRECIATE YOUR TIME AND ADVICE.

Follow up! Tested the project and it works amazing! I'm elated. Thank you Mark!

Hey hey! Glad if I was able to help. I appreciate you coming back in to keep me updated on things.

Pop back anytime we can help, OK?

Mark