Maybe this will help

来源: 于 2018-03-02 18:14:54 [旧帖] [给我悄悄话] 本文已被阅读：次

Inspect the vent pipes and try this before calling an expensive roofer.  Good luck.

https://www.homedepot.com/p/Oatey-1-5-in-3-in-All-Flash-Rain-Collar-14136/204719954