The Ontario Building Code | Chimney Caps

9.21.4.6. Chimney Caps

(1) The top of a chimney shall have a waterproof cap of reinforced concrete, masonry or metal.

(2) The cap required in Sentence (1) shall slope from the lining and be provided with a drip not less than 25 mm from the chimney wall.

(3) Cast-in-place concrete caps shall be separated from the chimney linerby a bond break and be sealed at that location.

(4) Jointed precast concrete or masonry chimney caps shall have flashing installed beneath the cap extending from the liner to the drip edge.