We're going to move our washer/dryer to the garage (the front loader needs to sit on concrete to keep it from shaking our house to the ground).
I'll need to add a washer drain to the garage for the washer. Because this will need a p-trap, my understanding is that it also needs to be vented.
I could go straight up into the attic then through the roof, but my question is: do I need to actually go through the roof? Could I instead have it go into the attic then 90 degree it out to the back, second floor wall? I can't find any particular code rules on if it has to penetrate the roof or not. This is a septic system, if that matters.
The reason for trying to avoid the roof is that I'd prefer to not climb up onto the roof...it's about 45 degrees and in the PNW so perpetually wet and mossy.