I went to my attic today and saw that all of the bathroom exhaust fan duct pipes are put loosely to the hole on the inside of the vent. Does this look right? I’m afraid this would blow air to the attic instead of outside. I looked up air vent images and they all have a pipe-like protruding part go through the wall to the inside, which is taped to the duct. Mine don’t have those things. Are there missing parts during installation?
It's kind of hard to tell exactly what's going on in that picture, however it looks to me like the rigid duct was just pushed up to the vent opening as you suspect. Can you move that rigid pipe pretty freely side to side?
I'd suspect that there is actually a duct starter from the vent, but that this rigid duct you see is bigger, so they just slipped it over. If it was the right size, they shouldn't have been able dent in the outer duct like that.
I would simply use proper duct tape (the more expensive, aluminum backed stuff available at the HVAC aisle of your local big-box store, not the cheap cloth backed duck tape sold in 10000 colors & patterns) to seal this off as best you possibly can to prevent moist air leaks into your attic.
You'll have to work hard on the right hand side to get around that stud there - someone did you no favors with their selection of hole location... But, the better job you do, the longer your attic insulation will last. You'll be buying the smallest size roll of duct tape they have, but it'll still be far more than you'll need for this, so go wild with it.
