DWV in home on slab

[Arvydas]

I recently bought a house built with all of the plumbing in the slab and did a whole remodel. It was a bank owned property built in the 50s, and needless to say I ran into quite a few head scratchers. As far as plumbing, I replaced all fixtures and traps. In doing so, I noticed that the only fixtures that seemed to be vented were the bathroom sink and toilet, via the main vent stack. All other fixtures drained directly down into the slab with no vent. Reluctantly, I just re-plumbed all traps as they were before and hoped for the best. About 5 months passed with no issues at all.

Recently, while running the washing machine there has been serious gurgling coming from kitchen sink, bathtub, and a floor drain for my hot water tank. At the same time, the bathtub began to drain very slowly. The main vent stack is clear, as I can see water flowing at the bottom of the stack when the toilet flushes and bathroom faucet is ran.

I believe I have a venting issue and have attached pictures of the kitchen sink, bathtub, bathroom sink, and laundry drains. The kitchen sink, bathtub, and laundry all drain down into the slab with no visible vents. The bathroom sink drains into the wall and is wet vented into the main stack with the toilet.

I cannot believe that these fixtures could have been piped in with no DWV. I'm can turn a wrench, but I am no plumbing expert. I'm wondering what I'm missing here, and what possible fixes could be. Any input is appreciated. Thanks.

 

[Reach4]

If you have a septic tank, get it pumped. If that is not the problem, get your drain pipes cleaned.

Vent problems don't cause slow draining.

 

[Sponsor]

 

[Terry]

The drain backing up means you may need to get someone in there and snake the line. It's not venting.
You do have issues with venting, but those issues would be the traps siphoning dry while draining quickly. A vent breaks the siphon, and keeps the gases from entering the home.

The tub drain. We don't mix ABS and PVC. Different materials and different glues for them.

 

[Arvydas]

I appeciate all the input. Snaking the lines is my next move. My main concern is the vigorous gurgling that occurs at the kitchen sink, bathtub, and floor drain when the washing machine drains. It's followed by the smell of sewer gases. That is what led me down the path of venting. Is that linked to the blocked drain line as well?

Also, would installing AAVs be the best solution for the venting issues?
Thanks, for the advice. These forums have helped me on multiple occasions. Re"Terry, post: 588605, member: 1"]The drain backing up means you may need to get someone in there and snake the line. It's not venting.
You do have issues with venting, but those issues would be the traps siphoning dry while draining quickly. A vent breaks the siphon, and keeps the gases from entering the home.

The tub drain. We don't mix ABS and PVC. Different materials and different glues for them.[/QUOTE]

The drain backing up means you may need to get someone in there and snake the line. It's not venting.
You do have issues with venting, but those issues would be the traps siphoning dry while draining quickly. A vent breaks the siphon, and keeps the gases from entering the home.

The tub drain. We don't mix ABS and PVC. Different materials and different glues for them.

 

[Terry]

My brother had a log cabin plumbed like yours. His washer also siphoned the kitchen sink trap.
Adding AAV's everywhere would help, sort of like manufactured home plumbing. You do need at least one vent through the roof for that to work though.

On my brothers place I added venting that that fixed it.

This is a pretty standard washer rough.
You should add a p-trap to what you have coming from the slab, and vent it to prevent siphoning. This vent is through the roof, or you could use an AAV above the flood lever of the standpipe.