I finally saw why those flexible flue liners keep failing after 5 years

Most guys are using the wrong mortar type for the top seal, and it cracks with the first freeze. What brand of high-temp mortar are you all using for that joint?

3 comments

3 Comments

amyh121mo agoMost Upvoted

Actually, the freeze isn't the main cause.

abby_morgan181mo ago

Disagree, it definitely plays a big part.

beth_park1mo ago

Ugh, this is like when people argue over what broke the TV. @abby_morgan18 is right, the little stuff adds up and then everyone acts shocked when it finally breaks.