New Tub with AFD?

Sterling/Kohler makes the tub my wife and I were looking at putting in. Our current tub was open on 2 sides, and didn't have enough headroom to use as a shower with a roofline getting in the way. I'm moving the tub location to the opposite wall as well as the sink. This will require new DWV plumbing. (The old stuff was VERY wrong, taking chunks way too big out of joists, etc, etc.)

This is a 2nd floor bathroom above the kitchen.
Anyway, I see that Kohler offers our tub in an Above Floor Drain option. This would be great as we'd otherwise have to go through the joists for a 5.5 foot run from the tub to the drain branch we want to tie into. (Kitchen ceiling below is only 7.5' tall, and I don't want to drop it any more to go under the joists.)

So, with a 5.5' horizontal run, I'd have to drop 1 3/8" in slope, right?

Has anyone installed one of these? I guess i can't visualize or quite figure out if the extra 3" would allow me enough room to run the drain plumbing through the wall without penetrating the floor.

Is there another option to NOT go through the joists? (Can I mount the tub on a raised up floor, etc?)

motosliders said:

So, with a 5.5' horizontal run, I'd have to drop 1 3/8" in slope, right?

Click to expand...

As long as the pipe is straight (not sagging), you would even be okay with a little less.

motosliders said:

Is there another option to NOT go through the joists? (Can I mount the tub on a raised up floor, etc?)

Click to expand...

Sure, and if you have the room, you could even extend that platform out along the edge of the tub and tile it to match.

tub

You still need a trap and that can create its own space problems.

OK, I'll look more into it. I'll have to look up that post.


That's what I was thinking, HJ. I didn't see how it'd really help.


If I do have to go through the joists, is there a simple way to do that, or will I end up with a coupling between every joist?