corner bead for drywall/cement board corner

[FJK]

Somehow, this has turned into an issue that I don't know the solution. Due to health problems, I had to start hiring guys to finish a bathroom remodel I was doing myself. The tile guys say this out of their scope of work, which I accept.
I had a painter finish off the drywall in my bath & he did a good job with the exception of an outside corner, where cement board on 1 wall met drywall on the other wall. He didn't install any outside corner bead. We have been using the paper/metal bead that is held on with drywall mud. Obviously, this won't work on cement board. What is the best way to install corner bead in this situation & what type of corner bead should be used? I need to get this resolved before the tile guys get scheduled in about a week.

Thanks, Jim

[Houston Remodeler]

Jim,

Is this outside the wet area? If it is, you can use the paper / metal tape on the corner. Just keep the drywall mud out of the wet area, which can be easily accomplished by masking off the area. You can tile over and / or waterproof over the drywall mud.

How is your shower being waterproofed?

[FJK]

The cement board is on the wet area, the drywall is on the dry area, forming an outside corner. Are you saying just use the metal/paper corner bead, install with drywall mud, even on the cement board. Then, just tile over the mud with thinset & tile.

[Houston Remodeler]

Jim,

So you're saying the last 1" corner of the cbu at the drywall will get wet? is this a tub surround? is there a shower door?

[FJK]

Yes, it is a tub surround. So, the first 1" of cement board at the corner, is outside the tub. Since it is outside the tub, I guess you could say that 1" of cement board is in a dry area.

[tiletime56]

Can you cut the cement board back?

[FJK]

It would be a major pain to cut back the cement board at this point & replace it with about an inch of drywall. The tile (bullnose) will run to the outside edge of the corner anyhow.

[Houston Remodeler]

Then you have 3 options:

A- tile the drywall outside the shower as a "picture frame" type installation

or

B- use L channel where the L channel is normal sized on the attachment side and 1/2" on the bottom L side, which tucks under the tile. Thatway there is no floating on the CBU side.

or

C- Use J channel putting the attachment side on the drywall, where the tile overlaps the bottom of the J channel

[mossypath]

I will never use a metal corner bead on a corner of a tub wall .
look at the plastic Tear Away L Bead http://www.trimtexinc.com/product_ca...egory&catid=28 if you are going to tile to the corner . It will give you a nice edge to finish to without bumping out the corner for your tile install . works great for soffits above tubs to.
I will always use plastic if water will be anywhere close to the trim. I cant tell you how many corners I have seen rusted out near the floor from water being splashed on the bathroom floor and wicking up the drywall.

[handymikey]

That's a great idea Tammara. I've used that product myself and it worked out very well. I wouldn't hesitate to use it for this application.

[FJK]

From C&R's options, I don't want A, so it looks like B or C. The post following C&R's also says use an L channel. Where I can I locally get this L channel? It sounds like the L channel has 1 leg the normal width of a corner bead & the other leg is short, like 1/2" to cap the edge of the drywall. Am I understanding this correctly? Also, this L-channel is all plastic, so it is just installed with drywall mud?

[Houston Remodeler]

You can buy plastic L bead at home burrito, or lowes, or a building supply store. Its fairly common.

Instead of installing it with screws or nails or just mud I prefer to install it with Corner bead adhesive spray (aka contact adhesive) as this does not deform the plastic, gives a nice straight edge and you can use a long level when installing it.

[pj4cks]

Hello folks,
Thought I would resurrect this thread a decade later to just say thank you. I had this exact same scenario and went with the L bead (tear away as well). It turned out great. This simple thread saved me from a sea of YouTube videos for this seemingly niche situation.

Thanks again!