I am trying to vent my sink which is going to be in front of a window that was just installed. Its the top floor of a split level home. The plumber told me I could not go through the (3)studs and have to do it in front of them. I now have to fur out the wall 2 inches. I have vaulted my ceiling as well and am not doing cabinets on the wall the vent is going up. It seems ridiculous there is not an easier way to do it. I thought I would just be able to have the pipe come through the floor and do a 90 where the sink goes while the vent continues straight up the bay, into the ceiling rafter bay, and out the roof.

your sink drain/vent will look like this.
you can run 60 inches from the sanitary tee (vent) to the trap with 1 1/2 inch pipe at 1/4 inch per foot slope.

you can not 90 the vent pipe until you are 6 inches higher than the sink.

Just for clarity the last sentence should end with sink overflow level

Thanks for the reply. You drilled through the 'king stud' of the window but put some plates on there it looks like. Will that pass in every town in MA?

i have done this dozens and dozens of times with never any problem from an inspector up here on cape ann.
the difficult part is getting the 1/4 inch per foot slope on the long hole thru 3 of 4 studs connected together.
of course it always seems that the carpenter always puts multiple nails just where we have to drill



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