Inline trap for washer - Limited space

[dBrent]

Hello, thank you for letting me register for this forum.

We have moved into a new house and once we started using the facilities a sewer gas smell became apparent in the laundry area. Blocking off the washing machine drain eliminated the odor. Using a snake and a remote camera I was able to determine that there is no trap in the washing machine drain. I've done a lot of DIY plumbing, but I am uncertain of how to fix this. I can put a trap in the wall, but the problem is that there is not enough room for a proper P trap. The drain line is straight down from the washer wall insert to the floor. Like this illustration. The left and right lines being the wall studs


The option I was trying to go with is this illustration, but it ends up basically being an S trap that I would like to avoid if possible.


The pipe is 2" PVC and there is no room to place a lateral span of any sufficient length between the trap and the drain into the floor.

I have seen the straight thru trap assemblies on various web pages, but I have been unable to find a source in the U.S. and those I did see are not 2". I was hoping someone with more experience might have a suggestion for me.

Thanks,
Brent.

 

[breplum]

You need a Tee fitting so that there can be a vent, even an air admittance valve (AAV), we also add a cleanout in most circumstances.
It is allowable to have a p-trap come out and be exposed on the outside of sheetrock/wall.
I recommend finding a good plumber via Yelp or Nextdoor

 

[dBrent]

Thank you for your response. I should have mentioned there is already a vent right next to this drain.

I considered having the trap outside the wall, but I was hoping to avoid such an unsightly solution.

 

[breplum]

I understand unsightly, but normally it is all behind the appliances, so nobody will ever see it

 

[TomFOhio]

Can you install a washing machine box some how?? Then you can keep everything in the wall

 

[dBrent]

I do have a washing machine box installed. The problem was it is directly over the drain in the floor. The wall has six inch studs, so a solution I saw elsewhere was to run the drain line through one stud giving me more room to make a more proper P trap.