The Ontario Building Code | Copper Joints Used Underground
7.3.3.12. copper Joints Used Underground
(1) Except as provided in Sentence (2), joints in copper tubes installed underground shall be,
(a) made with either flared or compression fittings, or
(b) brazed using a brazing alloy within the American Welding Society’s AWS-BCuP range.
(2) Compression fittings shall not be used underground under a building.
7.3.4. support of Piping