Can anyone tell me what these are? There are two of them protruding from the crawl space (sitting on the ground and caped on the sides) up through the walls and vented through the roof. They are made of ceramic clay and join together in 3 foot pieces. One whole stack was removed from the top of the attic and placed aside for the new electrical to be routed through it. At first I was thinking radon, but now i’m not so sure. This house was a flip remodel in Fresno , CA. They are not chimney stacks as the main chimney is centered in the home and none of the other rooms have fireplaces.
Looks like an old furnace flue. What did it look like from the roof?
It does look like an old flue pipe. Possible / likely asbestos containing material that’s not easily friable.
They appear to be, 24" inch long old clay chimney flues, used to line chimneys, bonded - sealed - wrapped in refectory masonry.
The circular opening is likely for the circular sheet metal furnace flue.
Just my 2 cents.