The Ontario Building Code | Materials

9.26.4.2. Materials

(1) Sheet metal flashing shall consist of not less than,

(a) 1.73 mm thick sheet lead,

(b) 0.33 mm thick galvanized steel,

(c) 0.33 mm thick copper,

(d) 0.35 mm thick zinc, or

(e) 0.48 mm thick aluminum.