I'm replacing a walk-in shower with a whirlpool tub 36" x 60". I have the foundation ripped up to move the p trap and raiser. The drain needs to stay centered where it is now which is 18" on center from the side wall and needs to move over toward the front of the tub to 4" OC from the front wall which the tub will butt against. You can see the rebar in the picture which the new drain will fit just about perfectly inside of (lucky me), so no worries there that I know of. My question is what is the best course of action to move the drain? I was planning on cutting the pipe off right before the trap and putting the reducer on there to bring it down to 1 1/2", then bring it out to center from there, install a 90 sweep then set the p trap and raiser right where I need them. Is this method okay? If this is okay, should I angle the 90 at all to put some pitch on that part of the line? Hope this all makes sense. Thanks

http://bellsouthpwp2.net/m/i/mike195275/drain.JPG

With a whirlpool tub I would not reduce to 1.5" . I can't really see that much from this one picture. Maybe I'm getting old but I get the sense that the right side of the picture should be at the top. What are wee seeing here?

Are you in canada or the US? Because 1.5" even 2" would work. But then again ballengerb1 has a good point about what are we looking at here?

After taking a second look I believe we are looking down into the pit you created. Looks like that lower 90 elbow is the end of your trap entering the drain line, right?

I am in the US, in Florida. The left side of the picture where you can see the rebar is where the front of the tub will be. That's where the drain needs to move to. The tub overflow kit is 1 1/2". Hope that helps.

After taking a second look I believe we are looking down into the pit you created. Looks like that lower 90 elbow is the end of your trap entering the drain line, right?

You are correct. The picture shows the trap and raiser. You can't see anything before the trap because it's under the foundation there, but I can get to it.

I think the elbow we see in the pic on the right is the drain you won't to tape into. Is it? If so I would change the elbow to the direction you are butting the drain. Work from there to where you need it. In Canada we have the option to have 1.5" to 2" I really don't know what it is for the US. Best of luck.

If the tub is set for 1.5" then you are going down the right path. Everything you describe sounds good and there isn't much need for slope since that lateral would be only a few inches in length,just be sure there is no drop. Do you have room for two 45s rather than a 90?

If the tub is set for 1.5" then you are going down the right path. Everything you describe sounds good and there isn't much need for slope since that lateral would be only a few inches in length,just be sure there is no drop. Do you have room for two 45s rather than a 90??

The lateral will be about 15", will a slight pitch hurt anything just to make sure there is no drop? Using 45's would be possible but probably tight. I have a 90 sweep already that I planned to use. I just want to make sure the setup I do is up to standards. If that requires 45's then I will use them instead.

With 15" you should try for a 3/8" pitch and I'd shoot for the two 90s if you can. The drain will scour better and less chance of grease and hair building up.

With 15" you should try for a 3/8" pitch and I'd shoot for the two 90s if you can. the drain will scour better and less chance of grease and hair building up.
I would have to agree.

Great answer.

With 15" you should try for a 3/8" pitch and I'd shoot for the two 90s if you can. the drain will scour better and less chance of grease and hair building up.

I'll use your advice and also assume you meant 45's. Thanks for you help. I'll be back when I'm ready to do the water supply lines.

Dah, sometimes I am trying to type faster than my brain. Yes, you have the right picture, two 45s would be better than a 90.