Does this look right to you?

Remodeling the bathroom, currently gutting down to the studs and found this.
First: The tub drain and vent. The wye on the drain pipe is rolled slightly so that the section that drains the tub is higher than the section going to the vent. I would think it should be the other way around. Should I cut that section out and redo it?


Second: If you follow the drain pipe toward the waste stack, it turns 45 dgrees to go from horizontal to 45 deg from vertical. An inch later there is a 90 ell to go from that diagonal to hoizontal and to change the direction perpendicular to the initial horizontal. Is this OK?

It wouldn't hurt to change it and do it right, but if it's worked without problems for 50+ years, it will most likely continue to do so. If money was not a big concern, I would probably replace it if I were doing my own house. You can sell the copper for scrap too. I can't tell what size you've got there, but it should be 1-1/2" or larger.

Jason

I don't know what your code says, but what you have is a line vent and not a fixture vent. You're right - it should be the other way 'round. And here, with the UPC code, horizontal vents are only permitted when there are structural conditions prohibiting using vertical tees. And, based on your pictures, it appears there is enough room for a tee and trap from the stack rather than a wye on the drain.

As to the combination of fittings further down the line: it's better if the forty-five isn't there because it's just one more fitting to have to clean around, but it isn't illegal. Vertical offsets don't count in change-of-direction considerations. You are allowed up to 135 degrees of change in direction without a cleanout. (Again, in UPC code.) It looks as if the drain was re-routed for some reason, based upon the hole in the joist that's empty.