How to replace a roof pipe boot with a cap
A pipe cap prevents a normal replacement boot from sliding over the pipe to seal holes leaking into the attic. Because split boots designed to wrap around the pipe are hard to find, homeowners resort to cutting a standard boot, duct taping it, and sealing it with roofing caulking.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Cutting a standard roof pipe boot to fit around the pipe and sealing it with duct tape and roofing repair caulkingDid this help you?
- 2Replace the pipe all the way down with PVCDid this help you?
- 3Replace the entire vent flashing instead of just patching the bootDid this help you?
- 4Cut below the rusted part and couple a new section onDid this help you?
- 5Call a plumber, then call a rooferDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I noticed that the boot on my CVENT-3 pipe had deteriorated and left a hole into my attic. Struggled to find a split boot to get around the pipe with the cap, so got a normal boot and cut it and then duct taped it and sealed with roofing repair caulking.”source ↗
“I am not great at maintenance and honestly have no idea what I’m doing, but this made sense. What am I missing/doing wrong?”source ↗
“Bought a house last year and this was on our list of problems from the home inspection. This pipe is busted on our roof. How do I fix this?”source ↗
Where this came up
People with this problem also raised
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