Code Library › Volume 1 › Section 9.21 — Masonry and Concrete Chimneys
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.21.2.4.Size of Chimney Flues

r1 (1) Except for chimneys serving fireplaces, the size of a chimney flue shall conform to the requirements of the solid fuel- burning appliance installation standards referenced in Sentence 6.2.1.4.(1) and Article 9.33.5.3. (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.
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Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.