[pburgh19]

I'm still banging away at my basement refinishing project. My latest hurdle is the location of the drain pipe in the bathroom relative to the height of the cabinet I want to use. The distance from the floor to the bottom of existing drain pipe opening is 20". The distance from the floor to the interior of the cabinet is 18". Obviously, 2" of space isn't enough for a trap. I could use a different cabinet that provides more vertical space, but I like the style with legs and storage shelf below.

I'm wondering if I can open the drywall, cut off the existing elbow, install another elbow angled vertically, add sufficient pipe heading up, then add another elbow leading to the inside of the cabinet. I've attached a crudely-illustrated photo of what I'm trying to describe.

Any issues with doing this? The pipe would be fairly close to the water lines.

 

[pburgh19]

As an add-on question... how much space would I need between the bottom of the cabinet and the drain opening in the back of the cabinet to provide adequate space for the trap plumbing?

 

[pburgh19]

Another way to ask this... is there any reason why the piping after the trap can't be lower than the trap itself? See my crudely-drawn sketch below

 

[huesmann]

^^^ That will create a siphon, which will obviate the reason the trap is there in the first plate—to keep the sewer gases out of your house.

If you're stuck with that location at the wall, you'll need to cut into the bottom of the cabinet, or possibly even the floor to get your trap below the wall connection.

 

[pburgh19]

^^^ That will create a siphon, which will obviate the reason the trap is there in the first plate—to keep the sewer gases out of your house.

If you're stuck with that location at the wall, you'll need to cut into the bottom of the cabinet, or possibly even the floor to get your trap below the wall connection.

Thanks... I felt like that was a no no. Can I not do my first idea and extend the wall drain pipe up a few inches so the p-strap exits ~parallel to the floor into the wall?

 

[Ghostmaker]

Your vent cannot be lower then the trap it is venting. So repipe the whole thing.

 

[HotRodx10]

Your vent cannot be lower then the trap it is venting.

Well said! I was struggling with how to convey that thought.