uglybus
New Member
I am in the process of turning a 20' x 30' room into a small 1 bedroom home. It is the first phase of a 3 phase project that will end up a 2-3 bedroom 2 bathroom home with a half basement. The part I am working on now is a half house on a block foundation with a clean crawlspace. The other half of the structure covers a 14' wide mobile home, which will be removed upon the completion of this first phase. I have it framed, the electrical in and am ready to rough in the plumbing. I have a pex manifold and a gas tankless water heater. I am fairly confident on the supply side, but have questions on DWV design. I have studied what I can find about the regulations, but find seeming contradictions. Maybe you can help me.
In the above image, all the plumbing fixtures being on the same level, do I need a 3" main vent protruding through the roof, or will a 1-1/2 or 2" inch suffice? I will be adding a second bathroom grouping at a later time and could either tie into this vent, or add another, but would prefer only one hole in the roof if possible.
Also I am unsure as to when to use a sanitary tee - except upside down in a vent system. Are they ever okay for use to connect a 1-1/2 or 2" horizontal drain pipe to a 3" horizontal drain pipe? I am confused, so am inclined only to use wyes, unless somebody can clarify. Thanks, Neal in Handy, Indiana
In the above image, all the plumbing fixtures being on the same level, do I need a 3" main vent protruding through the roof, or will a 1-1/2 or 2" inch suffice? I will be adding a second bathroom grouping at a later time and could either tie into this vent, or add another, but would prefer only one hole in the roof if possible.
Also I am unsure as to when to use a sanitary tee - except upside down in a vent system. Are they ever okay for use to connect a 1-1/2 or 2" horizontal drain pipe to a 3" horizontal drain pipe? I am confused, so am inclined only to use wyes, unless somebody can clarify. Thanks, Neal in Handy, Indiana
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