We currently own a 2-story duplex, and last winter we had water leaking in around a toilet vent pipe that runs vertical through the external wall, and out the roof about a foot from the edge. There is as much insulation as possible in the area, however the heat is causing the snow to melt, and creates ice jams, backing the ice up to the vent pipe, where it's entering. The ice only needs to backup about a foot before it reaches the pipe.
There is also another issue, where ventilation can not really happen with what's there - The ceiling in the top floor is only about 6'3". From what I understand there is room for insulation, and not much more for anything else. I think the correct and most expensive fix is to increase the slope, maybe sloping a 2x12 on top of the current roof, and adding in a vent on both sides.
Would it be possible to strip down to around the vent pipe, add a better boot, and then tar over the whole section of roof?
What's the best / cheapest way to fix the problem?
Attached is a pic of the problem.