The Ontario Building Code | Panel Cladding
9.27.8.4. panel Cladding
(1) Plywood applied in panels shall have all edges supported.
(2) Not less than a 2 mm gap shall be provided between panels referred to in Sentence (1).
(3) Vertical joints in cladding referred to in Sentence (1) shall be protected with batten strips or caulking when the plywood joints are not matched.
(4) Horizontal joints in cladding referred to in Sentence (1) shall be lapped not less than 25 mm or shall be suitably flashed.