13-23 Tubular sink waste

Question: 13-23Code Section: 7Date: 16 December 2013OBC 2006 Reference:

 Question submitted: Is this installation legal?

Interpretation: Companies have been making these types of fittings that connect fixture outlets to the drainage system for years. Most of these fittings conform to the CAN/CSA-B125 “Plumbing Fittings” as required by
However, the certification of a fitting is one requirement of the Building Code. Where these fittings are permitted to be used is also regulated by the Building Code (i.e. the installation of a fitting must follow the Building Code requirements).

This installation would not be legal as per OBC regulations, the appropriate code references to to apply are:

Division A – Conflicting Requirements
(1) In the case of a conflict between the provisions of this Code and those of a referenced document, the provisions of this Code shall govern. T and Cross Fittings
(1) A T fitting shall not be used in a drainage system except to connect a vent pipe.
(2) A cross fitting shall not be used in a drainage system. Assembled Pipe or Tubing
(1) Pipe or tubing assembled to comprise a standard drain waste and venting system shall be connected with drain, waste and vent fittings in conformance with Table

The Code Technical Committee acknowledges that based on over 20 different manufacturers of this assembly at a glance (brass, chrome, PVC, ABS ), these fittings are being known as the “baffled tee, diversion tee or centre outlet waste assembly” and may not be treated as a conventional  T or TY. Contractor consultation with the local building inspector is encouraged prior to installation.

The local authority having jurisdiction can accept either an applicable Acceptable Solution in Division B, or an applicable Alternative Solution that will achieve the level of performance required by the applicable Acceptable Solution in respect of the Objectives and Functional Statements attributed to the applicable Acceptable Solutions in Supplementary Standard SA-1.