Size of Chimney Flues

(1)  Except for chimneys serving fireplaces, the size of a chimney flue shall conform to the requirements of the solid fuel-burning appliance installation standard referenced in Sentence and Article

(2)  Where a chimney flue serves only one solid fuel-burning appliance, the flue area shall be at least equal to that of the flue pipe connected to it.

Article Ontario Regulation 332/12 Building Code,   O. Reg. 332/12: BUILDING CODE ( © Queen’s Printer for Ontario, 2021.