Is this an S-Trap? Please help!!

**derbarrett** · 03-12-2011, 04:35 PM

Hello All,

I am brand new to the plumbing world and have a couple of questions that I really need help with!!!
I am replacing the sink and vanity in my master bathroom, but there seems to be a small issue. The previous configuration had the sink drain into the floor instead of the wall.

1. All of the pics that I have seen online have the sink drain going into the wall (i this called a P trap?). In addition, all of the vanities that I have seen seem to be designed for the drain to go through the wall as well. Is my current configuration considered an S-Trap? If so, I have been doing some research and it seems like S-Traps do not meet plumbing code. Is this true?

2. My bathroom "floats" above my living room so there is huge I beam holding it up. This means that there is no room to run the drain pipe behind the wall because I would literally have to drill through the I beam. It seems like my only option to keep the configuration like it is now. Are there any other options?

3. I have attached a few picks. Pic 1 shows the floor drain. Pic 2 shows the I beam. Pic 3 shows the floating bathroom.

Thanks for your help!

**jimbo** · 03-12-2011, 04:44 PM

Well, you have no trap at all yet, but if you put a trap under the sink and then turned down right away into that drain pipe, then it will be an S.

**Cubey** · 03-12-2011, 04:47 PM

Perhaps you could do this:

[nevermind..]

**derbarrett** · 03-12-2011, 04:59 PM

So...... is there anything wrong with the sink draining into to the floor?

**cacher_chick** · 03-12-2011, 05:06 PM

As much as we dislike the thought of using an air-admittance valve, this would be the place which I would use one.

To do so, the existing pipe should be coming up out of the floor 17" On top of that install a sani-tee and trap adapter. Off the top of the sani-tee run a straight piece up as high as the vanity will allow and then install the AAV on the top. If you can get the AAV up higher by using a couple of 45's to clear the sink bowl, it would be even better.

An AAV may or may not be allowed by your plumbing code, but it will work.

**Cubey** · 03-12-2011, 05:39 PM

I'm wondering if it's tied into another drain like the kitchen sink. Does the kitchen sink have the same drain setup or does it have a p-trap? If the house is pier and beam or has a basement, I wonder if maybe there's a single p-trap someplace under the house or in the basement with the kitchen and bathroom tied together since the bathroom sounds like it's almost over the kitchen. When you run water in the kitchen sink, can you hear gurgling or noise in the sink's drain pipe? You might try that. Or even try pouring water down the sink drain pipe and have someone in the kitchen to see if it sounds like it's passing by near the kitchen sink's drain. Either way you might be able to hear water gurgling if they are connected together.

**derbarrett** · 03-12-2011, 05:43 PM

Please excuse me if I sound ignorant, but I am a newbie.

1. In the big scheme of things... why is it better for the sink to drain through the wall with a p-trap as opposed to it going directly into the floor? Doesn't the wall pipe eventually turn down to the floor anyway?

2. I would like to install a floating vanity. Is this even a option for me with my plumbing configuration?

http://www.tonusa.com/Pic/Pic/produc...000/t1000c.jpg

**cacher_chick** · 03-12-2011, 05:52 PM

The problem is you must have a trap, and that trap must have a vent. Without either, the sewer gas can come back up the drain and stink up the house.

Having the pipe in the wall allows a place for the vent pipe to run hidden up through the roof.

A floating vanity won't be too pretty with a big ugly drain coming up through the floor.

**derbarrett** · 03-12-2011, 06:22 PM

I believe that the sink drain is connected to the toilet and shower drain, and that drain is connected to a vent pipe.

I have attached a pic of what I think is a vent pipe in the bathroom

**derbarrett** · 03-12-2011, 06:24 PM

Hers the pic

**derbarrett** · 03-12-2011, 06:25 PM

Having a little trouble... here the link
http://img694.imageshack.us/i/img0485wp.jpg/

**dlarrivee** · 03-12-2011, 06:29 PM

Originally Posted by Cubey

Perhaps you could do this:

So instead of an s trap you suggest an s trap and two more 90s? Are you serious?

**Cubey** · 03-12-2011, 06:42 PM

Yeah.. not quite sure what I was thinking.. so nevermind on that. LOL However, what about this:

http://www.nachi.org/forum/attachmen...conversion.jpg

**dlarrivee** · 03-12-2011, 07:17 PM

More trap arm is better, but you're still not venting the drain properly unless you install a santee and at the very least an AAV as high up inside the vanity as possible.

Personally, I would be opening up the wall, especially if you want to end up with a nice looking floating vanity.

**dlarrivee** · 03-12-2011, 07:24 PM

Originally Posted by derbarrett

1. In the big scheme of things... why is it better for the sink to drain through the wall with a p-trap as opposed to it going directly into the floor? Doesn't the wall pipe eventually turn down to the floor anyway?

You would be venting the drain properly if the piping was in the wall.