I'm planning a plumbing run for a drain and I need to work out the details of the cost etc before I put together a plan. I think I have an idea but it might be all wrong so I want to run it by the experts here first.
The drain is going to be for a plastic basin that will be used for bathing dogs and it will have a good 20 - 25 foot straight run. 95% of the time it will only have to handle the drainage of the hand sprayer. I will have a cleanout (or 2) due to potential dog hair clogs.
First question: Refer to the first picture below...where the drain will come out of the wall (red circle) there is a small vent right there for my washer standpipe. Would this be a situation that I would be able to drain into this vent and create a wet vent? Standpipe in basement would be wet vented, basin 1/2 level up would be wet venting.
Distance from standpipe to stack:
Where the small vent attaches to the standpipe drain:
Second Question: The configuration of the rooms between the basin and the standpipe would make it very difficult to run a vent. Under what circumstances would an air admittance valve be allowed?
Thanks for any guidance and ideas. I live in Ontario incase rules on these two questions vary from place to place.
Edit: The basin will have an 1 1/2" drain, the vent is 1 1/2" and the standpipe drain is 2"