TechInstructor
Member
My husband and I are building a new house. Some of the work we've contracted out and other parts we are doing ourselves. After getting the revised estimate on having someone plumb the house, we decided that we could save a bunch of money and do it ourselves. Four years ago, DH re-plumbed all the supply lines in our current home with PVC and I assisted as a go-for, running to Lowes to get pipe, fittings, etc. so we've had some experience. And of course, I've always heard the that about all there is to know about plumbing is "Cold on the right, hot on the left, and sh!t don't run uphill." ; )
Well, now that I've been educating myself on drain, waste, vent systems and reading lots of plumbing codes, I've learned that there is a WHOLE lot more to it than is indicated by that statement! So I've been reading this and other forums, articles, books and as well as the code to try to learn how to properly design a drain, waste, vent system that will both meet the NC state building code as well as work properly.
I've drawn a plan using my CAD program and I would very much appreciate feedback from those of you who are experienced as to whether or not I have it right or if there is a more effective way to design the system.
Here is the floor plan. The fixtures that are shown will actually be on the main floor above the pipes and are only shown on this plan for reference. All pipes and fittings will be schedule 40 PVC. The brown pipes are the waste lines and the green ones are the vents.
Here is a section that shows the following from left to right:
The 3" branch drain runs from the toilet to the 4" soil stack where it exits the house (picts of that to follow).
Questions:
This section shows the branch drain again under the kitchen where it will connect with the soil stack. It shows one of two sinks we are installing.
Questions:
The shows the same area but looking through the exterior wall.
You can see where the sink vent exits the back of the cabinet and crosses over to join the vent stack. This is supposed to be placed 6" above the flood rim of the fixture, according to code, but because of the height of the counter and the windows, it may be a little short (I haven't actually measured it on site.). Any suggestions?
Lastly, here is the second kitchen sink.
After reading about AAVs on this forum, I think I may opt to run the vent pipe through the wall to connect to the vent stack that comes off of the soil stack. It's doable since the walls are all open.
Lastly, the slope I used for all waste and vent lines is 1/4" per foot, the waste lines sloping down and the vent lines sloping up. I'm curious as to how that will work with fittings. This is such a small slope, and it seems like if the fittings are not sloped that it will affect it.
Thank you in advance for sharing your knowledge and expertise. If anyone wants to see more of the house project you can view it on my blog at: http://cooperhomestead.blogspot.com/
Well, now that I've been educating myself on drain, waste, vent systems and reading lots of plumbing codes, I've learned that there is a WHOLE lot more to it than is indicated by that statement! So I've been reading this and other forums, articles, books and as well as the code to try to learn how to properly design a drain, waste, vent system that will both meet the NC state building code as well as work properly.
I've drawn a plan using my CAD program and I would very much appreciate feedback from those of you who are experienced as to whether or not I have it right or if there is a more effective way to design the system.
Here is the floor plan. The fixtures that are shown will actually be on the main floor above the pipes and are only shown on this plan for reference. All pipes and fittings will be schedule 40 PVC. The brown pipes are the waste lines and the green ones are the vents.
Here is a section that shows the following from left to right:
washing machine, lavatory, bathtub, vent, and toilet
The 3" branch drain runs from the toilet to the 4" soil stack where it exits the house (picts of that to follow).
Questions:
- Is 3" the proper size for the branch drain (the total DFU for the house is 14)?
- Is the vent coming from the bathtub drain necessary since it is only about a foot away from the vent for the branch drain?
This section shows the branch drain again under the kitchen where it will connect with the soil stack. It shows one of two sinks we are installing.
Questions:
- Is 4" the proper size for the soil stack?
- Is the vent tee in the correct place on the vertical stack (below all other tees)?
- Do I need the cleanout where the soil stack turns to exit the house?
- Once outside, the pipe will have another long sweep to before it runs to the septic tank. Do I need a cleanout there as well?
- I don't think NC requires a house trap but do you think one is needed? I'm assuming it would go on the line outside of the house.
**deleted picture to add one in a reply**
The shows the same area but looking through the exterior wall.
You can see where the sink vent exits the back of the cabinet and crosses over to join the vent stack. This is supposed to be placed 6" above the flood rim of the fixture, according to code, but because of the height of the counter and the windows, it may be a little short (I haven't actually measured it on site.). Any suggestions?
Lastly, here is the second kitchen sink.
**Sorry - had to delete the picture because I was over the limit of 4**
My contractor suggested using an air admittance valve or studor vent here. Is it acceptable to install the AAV under the sink?After reading about AAVs on this forum, I think I may opt to run the vent pipe through the wall to connect to the vent stack that comes off of the soil stack. It's doable since the walls are all open.
Lastly, the slope I used for all waste and vent lines is 1/4" per foot, the waste lines sloping down and the vent lines sloping up. I'm curious as to how that will work with fittings. This is such a small slope, and it seems like if the fittings are not sloped that it will affect it.
Thank you in advance for sharing your knowledge and expertise. If anyone wants to see more of the house project you can view it on my blog at: http://cooperhomestead.blogspot.com/
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