I’m trying to get my plumbing vents up into my roof joist bays. They’ll run halfway up the house until they hit a beam. I’m then going to level off the vents so they dip below the beam and connect perpendicular. They will be a soffit next to the beam to hide them.
The catch is that to angle them below the joists and maintain the proper 1/4”/ft slope, I need an angle of around 15 degrees. The smallest elbow angles I can find are 22.5.
1) do they make elbows with smaller angles than 22.5?
2) is there a different type of connector I should look for?
3) would it be ok to use two 90 degree elbows connected horizontally? I could achieve any angle with those but do end up with a lot of 90 angles in my vents. Is that ok?