The Ontario Building Code | Wood Column Termite Protection
9.17.4.4. wood Column Termite Protection
(1) Where termites are known to exist, exterior wood columns, such as porch supports, shall be,
(a) pressure-treated with a chemical that is toxic to such termites, in accordance with Article 9.3.2.9., or
(b) supported on non-cellulosic material extending not less than 150 mm above the finished ground and shall be located not less than 50 mm from the exterior wall of an adjacent building.
9.17.5. Unit masonry Columns