I want to install a washing machine in my shop. Where I want to put it, there is a sink drain right there. I haven't checked to see if it's 1 1/4 or 1 1/2 yet, but I know it's not 2" which is what I think is code, right? Can I just come out of that drain with a standard trap and mount my washing machine drain to that trap on the wall, or am I going to need to do something different? Is the vent that should already be there for that sink good enough for the washer or will I need something different? Thanks.

Pat

Yes, 1 1/4" and 1 1/2" drains would be too small. Your best bet is to stand washer next to the sink and drain it into the sink. That's how it is installed in older houses. And it will pass the Code requirement, too.

I agree unless you have access to a 2" or larger drain than might be handling the sink drain once it enters the wall.

There's not a sink there, it's just the drain hole in the wall with a plastic compression ring on it and some plastic wrap covering the hole. LOL I might have to tear open the wall to see what's going on but I might have to do that anyway when I re-route the existing 220 outlet for the dryer.

Ok, when you open the wall do as Ballengerb1 says: see if you have 2" pipe in there. If positive, than it is no problem to stub it out. However, there is a good chance that your new w/m will work ok even with 1 1/2" drain. Many older houses still use 1 1/2" drains and w/m work just fine.

Milo's statement is true. However, most homes have 2" washer drains and still have problems. I believe the 2009 code has upped the requirement to 3" because of too many issues in the past and newer machine pump a high volume. It pretty much boils down to the washer and how clean that drain pipe is inside. It isn't a fatal error to just try to hook up to what you have and if there is any back up then you can start tearing into the wall and drains. If you do go that route then shoot for a 3" drain.

Got this done today but we haven't put the washer in place yet. I've got my fingers crossed because the drain for the sink in the nearby bathroom goes down into a 2" drain after it enters the wall like Ballenger mentioned above so hopefully we'll be OK. I'll let y'all know how it works out!

I wonder what the three inch washer boxes will look like. I guess all washer walls will have to be 2x6 now? And you will have to cut studs just to fit the 3" p-trap? We better make toilet drains a 6" requirement. What are they trying to accomplish with a three inch washer drain. If a two inch washer drain is installed correctly, it will handle the load from any washer(as will 1 1/2 which is code in some states, not mine,lol.). Im curious to see if this new requirement gets put into our code. If it does, so be it, if it doesn't,, great. Sorry guys, I just had a tough one today, guess I'm venting a little. Take care.

Hi all:

Good points Lee!

I keep hearing about this 3" washing machine drain requirement from you Bob...I don't see it happening...;)

It may happen in a place like Florida where kitchen sinks and washing machines connect together, for example...but a washing machine drain BY ITSELF will NEVER need a 3" drain pipe At least I am willing to bet on it anyway!

Hey, just having fun, but until someone shows me something with concrete facts... I will always advise 2" drain for washing machine... PERIOD!

Remember... we have 1.5 " drains all over my state (and others) and all are working fine... even on newer machines as long as the drain and vent lines are clear.

Thanks... MARK

We have our cec(continuing education credits/class) coming up in May. I'm going to ask the instructor about this and see what he has to say. The whole purpose of these classes is to address current and future code changes. Should be interesting to see what he has to say about it.

On a side note, are you guys required to take this class? It just became manditory a few years ago here. All journeyman and master plumbers have to take it once a year to keep their license active. Apprentices are welcome to come to, but its not required for them.

It may happen in a place like Florida where kitchen sinks and washing machines connect together, for example... but a washing machine drain BY ITSELF will NEVER need a 3" drain pipe I agree with Mark about a three inch trap and stand pipe' but We have been making the kitchen/washer branch 3" for years down here in single family homes. We make the kitchen vent the main house vent and carry three inch all the way to the 4" main picking up the 2 "washer station on the way.
Regards, Tom

Hi Lee:

YUP! I'm required to attend a code update course once a year as well. The law just passed last year!

And I'll tell you guys...I know one thing about the washing machine drain pipe size... ;) It will never be in agreement across the country! That is the only sure thing... I swear! :)

Hi all:

Good points Lee!

I keep hearing about this 3" washing machine drain requirement from you Bob...I don't see it happening...;

I think he may have picked it up from me a year or so ago.

I sat in on a few IAPMO and UPC adoption committee's a few years ago where the issue was discussed.

It was bandied about for several days and then tabled (The appliance companies have a lot of money to burn).

As for fitting a 3" trap and standpipe inside a 2x4 wall.. .

I've done it in a few commercial laundromats without one single visible bump or protrusion.

Remember, Plumbers -- Your torpedo level is your best friend.

If it isn't in your hands -- Then it should be in your back pocket.

I remembered you mentioned it but didn't mention that because I didn't know when you would be around again... It is always a pleasure to read your perspective!

Thanks for the update!

No, we are not required to take the CEC classs in So.California.

We found out about Code changes the hard way: we do a job, have Inspector not to sign it off, he makes corrections, and then we have to comply with the corrections and call him back for re-inspection.

I wish they would print a flier informing us about new Code changes and mailed it to each licensed plumber. But I guess that would be too much to ask... :D

No, we are not required to take the CEC classs in So.California.

We found out about Code changes the hard way: we do a job, have Inspector not to sign it off, he makes corrections, and then we have to comply with the corrections and call him back for re-inspection.

I wish they would print a flier informing us about new Code changes and mailed it to each licensed plumber. But I guess that would be too much to ask .....:D

D00d.. .

Continuing Education Classes can be the difference between being sued for cause or having the case thrown out in prelims.

Required or not -- If they're offered, you should *always* take them.

Seriously.

I cannot stress this enough -- We live in a very litigious society -- Spend the money and (educate) protect yourself.

growler,, I can see it in a commercial laundry. But residential? And I have seen three inch pipes in 2x4 walls also, but the outside diameter of a three inch pvc fitting is closer to 3 3/4. Most people may not notice the bulge, but I would. Nothing makes me madder than when a carpenter puts in a 2x4 wall when a 2x6 is required. Then they complain because they have problems with sheet rock. Three inch fittings do not fit CORRECTLY in a 2x4 wall. Not to mention that a three inch P-trap in a 2x4 wall (in a residential home) will take up too much horizontal space(trap and tee). You would have to move or cut studs (allmost all of the stud, rendering that stud useless, or reframe just for trap tie in). Two inch traps are close in room with out drilling studs. Am I making sense, or is carpentry in homes done differently in other areas.

growler,,, i can see it in a commercial laundry. but residential? And i have seen three inch pipes in 2x4 walls also, but the outside diameter of a three inch pvc fitting is closer to 3 3/4. Most people may not notice the bulge, but i would. Nothing makes me madder than when a carpenter puts in a 2x4 wall when a 2x6 is required. Then they complain because they have problems with sheet rock. three inch fittings do not fit CORRECTLY in a 2x4 wall. Not to mention that a three inch P-trap in a 2x4 wall (in a residential home) will take up too much horizontal space(trap and tee). You would have to move or cut studs (allmost all of the stud, rendering that stud useless, or reframe just for trap tie in). two inch traps are close in room with out drilling studs. Am i making sense, or is carpentry in homes done differently in other areas.

Cardboard furring strips and a hanger who knows their trade.

'Nuff said.

I agree with Mark about a washer three inch trap and stand pipe' but We have been making the kitchen/washer branch 3" for years down here in single family homes. We make the kitchen vent the main house vent and carry three inch all the way to the 4" main picking up the 2 "washer station on the way. With the grease and fiber from the washer and the garbage from the disposal going down the same branch it only makes good sense. Does anybody disagree with that? Cheers, Tom

Mark and all, I started talking about the 3" washer drain some time ago after listening to Iamgrowler who mentioned it was proposed for 2009. I am not a plumber and would never shell out over $100 to buy a book. I do not know for sure if 3" ever made it or not and around here my town isn't even requiring the most current code as it is. I do know that the newest washer like a Maytag do pump out much faster than previous models so it stands to reason you will have issue with a 2" drain far sooner than a 3" drain. Codes are not static, remember Polybutylene, things change when the world starts to see problems. I need to shut down, the aluminium wires in my house are starting to heat up.

Well the 1 1/2" trap going into the 2" drain is working OK so far. They run the machine almost every day and it's been draining OK with no backups. Thanks for everyone's help! :-)

Thanks for the update Johnspop... lots of those connections working fine in my area, too!

Good luck!