Old plumbing stacks don’t provide the rubber gasket but depend on caulk or direct which could have worn away. This might be the source of a leak. Be sure to go along with a Kynar 500 paint finish equivalent in addition to a CoolRoof rated coloration To optimize the longevity https://nepeanglass04681.liberty-blog.com/31845120/5-easy-facts-about-jorgensen-roofing-described