11-11 Sewage tank rough-in

Question: 01-11Code Section: 7Date: 14 June 2011OBC 2006 Reference:;(2)

Question Submitted:
We need to put in writing an answer for these question because I get the feeling that plumbers
are getting away with a lack of responsibility in the rural areas……

(1.) When a bathroom group in roughed in for future in a basement where gravity drainage is not possible,

(a.) Do I need to vent the future fixtures?

(b.) Where do I drain the required floor drain?

(c.) Is a pump required in the sewage tank?

(d.) Must I provide a vent off the tank or can I simply provide a future vent as per .5.5.5.(1),(2)?


(a.) Yes, every waste pipe shall be vented when it is installed.

(b.) The required floor drain must drain as per

(c.) Yes, the pump is required.

(d.) states the vent must connect to the top of the tank and states the
minimum size of the vent is 2”.

Note: Div. A, all materials, appliances, systems and equipment installed to meet the
requirements of the Code shall possess the necessary characteristics to perform their intended
functions when installed in a building. Also Div. C,