The Ontario Building Code | Tanks
8.2.2.2. Tanks
(1) Subject to Sentence (3), a tank that is used as a treatment unit in a Class 4 sewage system or a holding tank in a Class 5 sewage system shall conform to the requirements of CSA B66, "design, Material, and Manufacturing Requirements for Prefabricated Septic Tanks and Sewage Holding Tanks".
(2) Subject to Sentence (3), material standards, access and construction methods and practices for a tank used for other Classes of sewage systems shall conform to the requirements of CSA B66, "design, Material, and Manufacturing Requirements for Prefabricated Septic Tanks and Sewage Holding Tanks".
(3) Tanks referred to in Sentences (1) and (2) are not required to conform to the requirements of Clause 10.2.(j) of CSA B66 "design, Material, and Manufacturing Requirements for Prefabricated Septic Tanks and Sewage Holding Tanks".
(4) Sentence (2) does not apply to a tank that is an integral part of a prefabricated Class 1 sewage system.
(5) Access openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings shall be located to facilitate the pumping of all compartments and the servicing of the inlet and outlet of each compartment not accessible by removal of the tank top or part of it.
(6) A tank shall not be covered by soil or leaching bed fill having a depth greater than the maximum depth of burial that the tank is designed to withstand.
(7) A tank shall be securely anchored when located in an area subject to flooding or where ground water levels may cause hydrostatic pressures.
In Plain Language
Tanks used in a private sewage system, such as septic and holding tanks, must meet the general construction and installation requirements set out in this article.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.