Help with DWV Layout in residential new construction

[Jayjayla]

Hello,

I am building my own home in rural Idaho. I am looking for some expert feedback regarding the DWV layout I have drawn up for the place. I attempted to post this a few days ago, but did a bad job getting a good pic of the layout posted with this request. I'm hopeful I am doing a better job today!

The home with have finished concrete floors, so I want to make sure I get it right. My friend told me about this forum and how much it has helped him over the years. I appreciate the help.

Thanks,

Mike

 

[Jeff H Young]

An unusual house one bedroom?, the space between the bedroom and garage could have added square footage.
something strange about the plumbing layout .... it will never look like that plumbing is run either straight line 45 degrees or 90 , occasionaly 22.5 degrees so those bastard angles wont work. layout running around to the laundry and garage sink kinda wiered. oh another thing your plumbing trench needs to be away from a paraelle footing. a few pointers

 

[Sponsor]

 

[James Henry]

Your plan basically works it just needs a few changes. The washer stack and drain need to be 3". The farthest bathroom will have the lav arm drain into the vertical wet vent with a Santee then the shower will drain into a Santee then the toilet below that will drain into a Santee then a sweep below that into the main drain. Then all the other drain depths will be figured from there. If that makes the drain to deep then you will have to do it another way. If you're septic tank will except a 4" drain I would transition to 4" between the two bathrooms. People will say you don't need 4" but I prefer trouble free drains. I would also increase the kitchen drain, it will get a lot of grease in it.

 

[John Gayewski]

One tip. Make sure your septic tank is deep enough, to keep your plumbing piping low enough, to give yourself plenty of elevation and slope. With your vertical wet vents you can run each bathroom onto a small stack as long as your deep enough to stack fittings on top of each other.

I will disagree with up sizing piping. I went to a call last week where every bit of the customer's underground piping was backed up with toilet paper. It had to be one year or more worth of sewage stored in her piping. She had 4 inch piping that turned to 6 inch piping right outside her house. The water from flushing a toilet was a tiny stream flowing at the bottom of the pipe. None of her solids could travel to the nearest manhole. This i system was way over sized. We ran a camera through the whole system out to the street and couldn't find a sag or obstruction or break anywhere. It was simply having a pipe that was two sizes too big, which slowed the travel speed so much that nothing could get to the end except just plain water. There's no fix for this other than to flush her piping periodically with lots and lots of water, or run smaller pipe.

 

[Jeff H Young]

Upsizing everything sounds Loco, 2 inch too small on kitchen? we need 3 inch to a washer? 4 inch main overkill but understandable if you really want a 4inch main but run it through the house to other side and put a clean out on it there . but we are talking unnessesary BS.
I agree with John that a house built as he noted could cause this, the lady might use a ton of paper too but the water has to have a certain velocity if the water dosent move nothing moves bigger diametor decreases the velocity if not enough water goes down the drain