Basement Sink Installation - Indirect Waste Plumbing

[Obi Ogunjobi]

Hello,

I am working on adding a wet bar in my basement and have ran into some plumbing questions for proper installation. I have a floor drain near the utilities equipment which connects to the sanitary sewer and am wanting to plumb the new sink drain into it due to proximity. I don't want to break up the concrete if I don't have to so I am curious if I can just have the sink drain plumbed to the top of the floor drain (open ended). Is it per code to plumb a sink to this drain without a direct connection? I've done a little research on this and found indirect waste installation is used from commercial sinks but wasn't sure if the same concept applied to residential installation. I also found some information on needing at least a 2" air gap from the floor drain. If I am able to have the sink drain open ended to this floor drain would I still need a vent line? P-trap?

Any insight / advice is appreciated.

 

[WorthFlorida]

You are referring to floor sinks and it must be tied to the septic system. You'll need to break up some concrete to install a proper floor sink, just dumping water over the drain won't cut it. The floor drain must have a trap and installing the floor sink the drain pipe may not be low enough. You can install the floor drain several inches above the floor but you lose a floor drain. You can extend the water heater pressure and relief pipe over to it.

Either way you'll have this pipe several inches above the floor that be a trip hazard. A trap will not be needed at the sink. The 2" air gap prevents any sewage backup from entering a sink or appliances, very important in a commercial kitchen. Should cleaned items remain in the sink and the sewer backs up then drains down, it may not be realized that the sink and items are now contaminated. Google "floor sinks" for images. There are dozens of shapes and sizes.

 

[Sponsor]

 

[James Henry]

The existing floor drain more than likely has a trap, the only thing that I don't like is the tripping hazard. you would also need a trap under the sink because the indirect waste line would be longer than 2 feet.

 

[Terry H]

It depends if you want it to code. If you don’t care about meeting code then I would say yes dunk the sink in it and keep moving but if you are trying to meet code then you’ll need to make some changes.

We are allowed to turn a bell reducer upside down and that satisfies the problems you face right now. However, that applies to condensate lines etc not what you are doing. Honestly probably the safest bet is a floor sink as was said above. It wouldn’t be too much work and would definitely satisfy code.

Again, it depends if you are worried about code or not. I would personally just dump it in there if it were my own project. If I had to update down the road if I sold the property then so be it.

 

[Obi Ogunjobi]

The existing floor drain more than likely has a trap, the only thing that I don't like is the tripping hazard. you would also need a trap under the sink because the indirect waste line would be longer than 2 feet.

James - thank you for the information. I have some ideas to minimize the tripping hazard but it will still be there if I decide to not break up the concrete. I wouldn't need to install a vent line / mechanical vent to this drain since its open ended right? I don't foresee any vacuum issues with this.

 

[Obi Ogunjobi]

Ter

It depends if you want it to code. If you don’t care about meeting code then I would say yes dunk the sink in it and keep moving but if you are trying to meet code then you’ll need to make some changes.

We are allowed to turn a bell reducer upside down and that satisfies the problems you face right now. However, that applies to condensate lines etc not what you are doing. Honestly probably the safest bet is a floor sink as was said above. It wouldn’t be too much work and would definitely satisfy code.

Again, it depends if you are worried about code or not. I would personally just dump it in there if it were my own project. If I had to update down the road if I sold the property then so be it.

Terry - thanks for the information. Would a floor sink be required over the apparatus James shared?

 

[James Henry]

The apparatus I uploaded attaches to the floor drain grate. They have many styles. Just Google indirect waste. You don't need a vent.

 

[Obi Ogunjobi]

The apparatus I uploaded attaches to the floor drain grate. They have many styles. Just Google indirect waste. You don't need a vent.

James - thank you for the help. It is greatly appreciated.