Visited a old house in Portland last week and saw something weird with the flue lining

I was out on a job in the northwest part of Portland, one of those old craftsman homes from like 1910. The homeowner wanted me to check the chimney before they started using the fireplace again this fall. When I got up on the roof I noticed the flue lining was done with some kind of terra cotta tile I've never seen before. It was all cracked and heaving in spots, like someone had tried to patch it with mortar that didn't match. The whole thing felt off, like a half measure that was gonna cause problems down the road. Has anyone else run into weird old flue materials that just seem to fail in strange ways?

2 comments

2 Comments

ray_webb63d ago

Man that sounds frustrating, I've seen similar stuff in old Portland houses where people tried to patch things up with whatever was handy and it just makes a bigger mess later. The terra cotta tiles from that era can be really brittle too, so when they start heaving like that it usually means moisture got trapped behind them somewhere. Hope you gave the homeowner a heads up about getting that properly fixed before they light a fire in there.

grant_perry3d ago

@ray_webb6 is right on the money with moisture being the culprit. I actually read somewhere that old terra cotta flue tiles from the 1910s were made with a lower fire clay content, which makes them soak up moisture like a sponge and crack in freeze-thaw cycles. That patch job with mismatched mortar probably just made it worse by trapping water in there instead of letting it breathe.