drain-waste-ventplumbing
The lead boot around the waste vent has worn away. I have no idea how it happened, but I need to fix it. I was thinking of just buying another boot, cutting the bottom off, cutting the top of the existing boot off, and sliding the new boot over the old one.
I that a good way to fix it? If so, should I affix the new bolt to the old one somehow? If not, what is a better way to fix it?
Cut where marked, but adjust the location so you've got clearance to work later.
Seeing as you only need a couple of millimeters, you might be able to get away with buying only the coupling connector similar to this:
So a good straight cut where marked, insert the connect and solvent weld it back into place.
Take the cut piece in with you, and just make sure you've got a snug dry fit in the store. No need to actually figure out the exact diameter. Just buy the piece that fits.
Throw four 45s at it and get vent out of the way. Mount new work box in center. Use Acme cable stretchers ;-).
How to mount new box, you ask? How about toenailed jack stud floor to ceiling.
Best Answer
From the photo you posted I can see you have a different problem from what you may think. The reason the vent pipe is damaged is because a "critter" has ben gnawing it away!
The most likely suspects in the animal world (in N.A.) would be in the rodent species: squirrel, rat, chipmunks, porcupines to name just a few. You can see the small serration grooves cut by their continually growing front and lower teeth.
What is extremely astounding is that the material is lead. A soft metal! You have a very determined and serious critter wanting 'in' to your house! Normally I would suggest en-circling the pipe with a wire mesh, but I would think it could rip through it and come back for seconds!
Repair or replace the vent as easiest and best you can. To stop the chewing apply a coating of roof patch to the pipe, covering it completely. I would try to catch the pest to prevent it from future damage elsewhere and from infiltrating your home.