My project planning is blocked by my limited understanding of the structural components in this space. I've had a few electricians walk through to quote the job, but didn’t share details on how they would do it.
I do not want to cut the tile because I lack experience with DIY and I think that would be too complicated with the wiring, etc. So I’ve ruled out venting through the tiled wall directly outside. Also, code requires these vents be installed a minimum of 3 feet away from windows.
I have considered venting through the wall right next to the tile. This may work, however the vent would likely terminate very close to the wooden support beams of the stairs which go to the upper unit and would face the underside of the stairs. It's worth noting that the staircase structure is not well protected from moisture and is already compromised (showing evidence of rot). Perhaps this would work if I could control the direction of the vent.
I was hoping it might be possible to install the fan in the ceiling and route the ducting out through this soffit. I would not vent into the soffit, but through it. I am concerned that this would introduce moisture into through the vented portions of the soffit, but I would look for a vent cap shaped to direct air away from the house rather than straight down. Venting through the soffit is technically permitted, however, it seems that this is not considered best practice.
But I am not sure if this protrusion in the ceiling is part of the construction of the stair landing above (which leads to the upper unit in this duplex) or what it is? I don’t want to just start cutting into a mystery spot in the ceiling. It was suggested that I purchase a bore hole camera and I am researching that right now.
The bathroom floor joists run the opposite direction from the rest of the house, they run parallel with the window wall. However, the pitch of the roof indicates the rafters run perpendicular to the window wall so I assume the ceiling joists do as well.
I’ve been pouring through articles on all the major DIY websites and watching videos, but this is situation specific so I was hoping someone on here may be able to identify that ledge thing for me so I can decide if it can be used for ducting exhaust.