I'm not going to get my new siding in behind the PVC drain. I need to move it out around 1" or so.
This is what I'm looking at.


I'm thinking of cutting the pipe right at the elbow (where the arrow points).
I'd then attach a new elbow and up length. I am a little concerned that, if I cut at the elbow, and attach a new elbow, I'll be moving the pipe around two inches away from the wall, which might be too much.

Do you have any suggestions on how I should handle this?

Also, what cement would you recommend? I do have Oatey Purple Primer, but I need a new can of cement.

Thanks in advance.

 

If you cut there the pipe will move the 1" from the edge of the elbow plus the straight length inside the elbow, so approx 3-4" depending on the size of the pipe.

You want to rebuild the vertical portion with the elbow including a small section of pipe and a coupling then make the cut further away to just move the pipe the 1" needed.

 

Thanks @Marq1 & @ray2047
I didn't realize that so much of the straight pipe was slipped into the elbow. I was thinking it was only about 2".
The vertical section is a about an inch shorter than it should be too, so I'll probably rebuild the vertical section when I shorten the pipe.
BTW. It is 4" pipe.
Oh, any suggestion on the cement? Should I try to find a heavy or slow(er) setting cement?

 

For your application what every they have will work for you!

 

I have deleted my reply because I'm not sure it would work.

 

You may find that shortening the horizontal line will affect the alignment of the downspout fitting into the vertical that you show in the picture. By cutting out an inch of that horizontal, you are pulling the vertical away from the wall on a diagonal and not perpendicular to the wall. It may not be enough to affect the fit but it should be considered. From your original post, it sounded like you wanted move the vertical section away from the wall at a 90 degree angle (perpendicular) to be able to fit siding behind it. you might consider using 2 opposite 45 degree fittings on either the vertical or the horizontal to keep the alignment.

- Peter

 

Thanks @Marq1, @ray2047, & @pjaffe,

@Marq1, It's good to know I won't need to be too picky about the cement I choose.

@ray2047, I think your approach would work if I allotted for additional length that the coupler would introduce. It would also require enough "wiggle room" to get both sections of pipe into the coupler.

@pjaffe, you bring up a very good point about the fact that moving along the diagonal to get further from the wall also moves the vertical section further to the right. Assuming that the angle of the pipe, relative to the wall is 45 degrees, I could calculate how much to remove of the existing pipe in order to bring me 1" further from the wall. To locate where I need to cut the existing pipe, I thought about it as if traveling along the hypotenuse of a right triangle. I can think of the new location as being a 1" side of the triangle (side "a"). The other side of the triangle represents how far to the right the vertical section will be moved (side "b") Since it is a right triangle. side a = side b, so side b is 1" (i.e., for every 1" further from the wall, my drain moves 1" to the right.
Using the Pythagorean Theorem, I could calculate how much of the current horizontal pipe needs to be removed (side "c"). Side "c" equals the square root of 2 or around 1.4".
I think that a 1" move to the right will be easy to accommodate.