Vent Design Help

[Jennie McNeill]

I am building my own tiny-ish home. I am ready to run the plumbing and have some questions about venting. There will be a shower, a commode, a washer, and two sinks. Ideally, I would like to run just one 3" vent stack through the roof. I was going to wet vent everything but, reading the codes looks like I can't do that with the washer and kitchen sink because they can't be in line with the commode in a full wet vent system. Can I wet vent my shower and commode into the vent stack under the house and then dry vent the washer and two sinks into the same vent stack in the attic space? Building is in North Carolina. I have attached a rough drawing of the layout of the fixtures. Thank you!

 

[MicEd69]

You need to show your intended plumbing runs. And based on your description, I'm not sure if you totally understand what wet venting and dry venting is.

Were you thinking you could run all the drains into the main sewer and that the vent stack would vent everything? A vent connection, wet or dry, need to be within specific distances of the P-traps the vent is serving based on the size of the drains. Dry vents need the be run vertically or no more than 45 degrees off vertical until they reach 6" above the flood level of the fixture they are serving. Wet vents don't have that restriction, but there are still rules that must be followed for wet vents.