Plumbing for 20x30 1-1/2

[Micky]

Are there any plumbers in the house?

I am attempting to layout the plumbing.  I would love any feedback.  My knowledge of plumbing is that the stuff flows down.  Other than that I have been trying to read up to keep things to code.

I am in Idaho.  There are no local inspections, but I have to pass the state inspection.  Idaho follows the UPC with the following exceptions http://www2.state.id.us/adm/adminrules/rules/idapa07/0206.pdf

There are a couple of strange things.

- The 2nd floor bath is over the exposed beam ceiling.  So I am trying to hide the plumbing.  I am using a floor mount - back outlet toilet.  I am also raising the shower to put the drain line under it.

- There is going to be a floor drain in the crawl space under the 1st floor bath.  This is so I can easily drain the water heater to winterize the cabin.  The state also requires a provision for a water softener installation.

-  I am trying to keep one roof vent since I am in snow country.

Here are some pictures.  The magenta is 3" pipe, blue 2" and green 1.5".

Also, I have a .pdf file you can download. http://www.geocities.com/merritt000/plumbing_20x30.pdf

EVERYTHING:


1ST FLOOR BATH


2ND FLOOR BATH & KITCHEN


Once I get things figured out, I will be happy to share what I have with other people building the 20wide.

Thank You

[glenn-k]

I'm a GC with some plumbing experience, Micky but not a real pro.  I like your drawing.

One thing,  it looks like some of the small vents are facing down where they connect to the main vent - They should point up.

One thing I noticed in the exception link you posted, but I don't think you have a problem with is:

12. Section 703.1 - Underground Drainage and Vent Piping. No portion of the drainage or vent
system installed underground, underground under concrete or below a basement or cellar shall be less than two (2)
inches in diameter. (3-15-02)

You may check for it though.  

I see you are allowed to use Aquapex.  Were you going to?  I did- it's great.

One other point I remember from someone else's posting--If you can get the vent to the peak of the roof, sliding snow and ice won't tear it off.

It looks like you have some wet vents (example - shower raised - second floor - the toilet flushes down the line used as a shower vent- you could simply put a san-tee in the shower line and the main vent above the toilet and connect them together -another - upstairs sink flows down the vent for the kitchen sink), but the exceptions have something posted about allowing it in some cases.  Looking more -it looks like there are other areas with the same problem. If not covered by the exception they would have to be changed.  I'll have to re-read that exception to try to figure it out.  I don't think we are allowed any wet vents here, but I haven't seen the current plumbing code.

Here is the exception - seems clear as mud to me.  Maybe it allows it - anybody know?

21. Section 908. Exception - Vertical Wet Venting. A horizontal wet vent may be created provided it
is created in a vertical position and all other requirements of Section 908 are met. (7-1-98)

It looks like what it may mean is that the example of the kitchen sink would not be allowed because there is horizontal piping above it- the shower one is also questionable due to horizontal waste line used as vent - probably not allowed without the fix I mentioned.

[n74tg]

Great drawing -- what software did you use?

[Micky]

Thanks Glen,  I changed the upstairs shower.  I also think I remember reading something about not being able to add any fixtures downstream of a toilet in a wet vent?  This should fix that.

I am also confused about being allowed a horizontal wet vent as long as it is vertical.  I think this may have to do with branching off a horizontal vent at 45 deg or more?  I figure once I get it where I am happy, I will ask the inspector to clarify.  Or maybe I will have him look over the plans so I don't have to change things later.

I think the 2" only applies to if the pipe is burried.  I am over a crawl space.  I would think the 1.5" bath pipe should be OK.

I am using aquapex.  This should make installation a lot easier.  Also, I like the idea of being able to shut off zones I don't need.  When we use the cabin it the winter I can  only turn on water to the toilet and sink.  That way I don't have to worry about re-winterizing the washer and dishwasher.  Also, I think it will be easier to run all the lines so they can drain.



n74tg, I used a CAD program called SolidWorks.  It is very much overkill and took a while, but it makes visulizing it much easier for me.

[Micky]

OK, I was doing some more reading.  Per the UBC, it looks like the make length for a wet vent is 6'.  Also, "all wet-vented fixtures shall be within the same story.

I will have to change the kitchen sink.  I will get it reposted when I am done drawing.

I thought plumbing was supposed to be simple.  "stuff flows down hill, and don't chew your nails"

[glenn-k]

Thinking a little more about it, Micky, I've always just made sure I never had a wet vent so that I never had to worry about their interpretations of the exceptions.

[glenn-k]

I am now remembering why I like Aquapex so much -- I plumbed the water lines for the new bathroom and laundry in less than 2 hours - hot and cold.