Across the joists lay a.
Attic vent pipe leak.
If the rubber boot is cracked rotted away or torn.
The immediate thing to do is to contain dripping water from the leak.
But make a big oval hole going down.
When this happens the water can seep into the house along the pipe.
Make a temporary patch.
Remove debris make sure your roof valleys are clear of debris re shingle valleys valleys may need to be reshingled with new ice and water shield put in place.
Do not cut any supporting beams or rafters.
The water entry point may not always the same as where the water drips.
Attic condensation is due to humid air leaking or vented into the attic.
Then you can easily cut the pipe lower in the old area and join it up with the new vent pipe.
Here are four common problems that can cause water to leak around vent pipes.
Quick fix from inside contain dripping water.
Areas where leaks have.
Find the water entry point.
Then cut the pvc lower down and properly connect it to the vent so no pressure is on any joints and is sloping downward.
Typically vent pipe leaks occur at the collar surrounding the base of the vent pipe where it breaks through the surface of the roofing material.