Potential problem with cement board installation

[TGrom]

We are renovating a bathroom. The old bathroom had a one-piece fiberglass alcove tub/shower surround which we tore out, and we plan to replace this with an alcove tub and then tile the walls. However, in one corner of the alcove, there are some pipes that interfere with the placement of a 2x4 to screw the cement board to. My question: how much of a problem is this?

In the old installation, they sistered a 2x4 to the top of a stud on the perpendicular wall to fix the drywall to, and I could extend that down by a foot or two. But that bend in the pipe is right about at 5' high, so about 46" above the height of the top of the tub, which means about 46" of cement board would not screwed down on the edge. The pipes are such that, if I installed an additional 2x4 as close to the pipes as possible, the cement board would be screwed down 5.5" from the edge of the board. Is that good enough for a solid substrate for tile installation? Thanks for any help!

 

[Cacher_Chick]

You could jog the left pipe over with a pair of 1/8th bends so that you can get another stud in there.

 

[Sponsor]

 

[Jadnashua]

Have you got enough depth to put some cleats on the sides of the studs in that bay, then install some ply over it so that it is flush with the front of the studs? That would give you a surface you could screw to that would be fairly solid. You'd probably want at least 1/2" ply, but it looks like the pipe is at least that far from the front of the studs. Go thicker if you can.

CBU isn't all that strong. It's big main purpose is that it's a good surface to tile to and is not damaged by getting damp.

 

[TGrom]

Jim, that seems like a good suggestion, but unfortunately, in my case there's not enough depth in front of the pipes for a sheet of much about anything. I think I can fix a short 2x4 down between the pipes, and I guess I can deal with the top section with a sistered 2x4. A little worried about everything being in plane, but hopefully this will work. Thanks.