QOD for 9/3/06 Plumbing

Hi to all,

Here is todays question.



Picture courtesy Charles Buell


Thats one of those inline traps right.

Lousy supports and not enough of them . Roy Cooke

Hi to all

the correct answer to this is:

**1 in 96



Ontario Building Code 1997
says Minimum Slope and length of Drainage pipes
(1) Every drainage pipe that has a size of 3in. or less, and every fixture drain shall have a downward slopein the direction of flow of at least 1 in 50
Strange that there can be that much difference in our codes .
Roy Cooke

This is from the IRC:

“Drainage fittings shall be designed to maintain one-fourth unit vertical in 12 units horizontal (2-percent slope) grade.”
“Horizontal drainage piping shall be installed in uniform alignment at uniform slopes not less than one-fourth unit vertical in 12 units horizontal (2-percent slope) for 2 1/2-inch (64 mm) diameter and less, and not less than one-eighth unit vertical in 12 units horizontal (1-percent slope) for diameters of 3 inches (76 mm) or more.”*

1/4" per foot for all drains min.
1/8" per foot for all Vents min.

I even own a level for plumbing, it has a second set of markings for 1/4" per foot slope.

It is very important to read the complete question. I failed to do that and choose 1/4 inch. This is the kind of question you have to look out for when taking a certification test.

Same here.:frowning:

Hi to all,

that was a little mean of me, but proves the point that Greg stated.

This was one of those questions that is designed to be wrongly answered, and no it isn’t a trick question, it is corrected worded.

BTW, the full explaination is to be found in IRC 3005.3 or UPC 708.0