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Title of Question:

How To Repair Roof Leak Around Plumbing Vent Stack


Name: Peter Kahn  City:

Question: My roof leaks around a 4" cast iron plumbing vent. I have applied roof cement which makes a temporary fix, but the leak returns eventually. I would like to know how the flashing and shingles should be installed so that I could remove some of the shingles and attempt to reinstall everything correctly.


Name: Deck1ng | Date: June 7, 2004, 13:31
Answer: Here in the UK we use a Lead Slate, which is a 2' sq of lead with a 4"/100mm lead pipe soldered to the center. This is placed over the stack pipe and the tiles layed as normal incorporating the lead. his makes a perfect patch with is totally leak proof, Maybe you use something similar, but just haven't found it yet!


Name: Tony Hoch | Date: August 27, 2004, 9:40
Answer: Check at the lumber yard or where you purchase roofing supplies and as for a vent stack boot. There is an EPDM rubber boot that streaches and seals around the pipe without the use of tar. Make sure you clean the pipe so you get a good seal. Make sure the metal flashing part of the boot goes up under the shingles so the water is shed properly.