# Do I tape gap between drywall and hardibacker?



## Starrgazer (Jul 1, 2012)

I'm remodeling my bathroom and going to install ceramic tile on my shower walls. One of the hardibacker shower walls meets up with the new sheet rock. I have a gap that's about 1/4" wide between the hardibacker and sheet rock. Do I use drywall tape and mud to fill this void or the hardibacker tape and mortar to fill it? The ceramic tile is going to end right were the void is so I'm trying to find out how to fix it properly so that the tile adheres. Thank you


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## jschaben (Mar 31, 2010)

Starrgazer said:


> I'm remodeling my bathroom and going to install ceramic tile on my shower walls. One of the hardibacker shower walls meets up with the new sheet rock. I have a gap that's about 1/4" wide between the hardibacker and sheet rock. Do I use drywall tape and mud to fill this void or the hardibacker tape and mortar to fill it? The ceramic tile is going to end right were the void is so I'm trying to find out how to fix it properly so that the tile adheres. Thank you


I don't think I would have planned the layout such that the tile ends right at the edge of the backer. No real good reason, just my intuition. If you mud and tape that seam, won't the tile need to adhere to the drywall compound? At this point, I'm thinking a flexible caulk would be a better choice to plug the gap. Get as little on the backer as possible. 
I'm sure you will get some pros to weigh in here shortly.


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## chrisBC (Dec 28, 2010)

That's pretty typical, usually I see it get taped and mudded. However you only really need to feather out where the painted wall will be once it is taped, I wouldn't go mudding all over the backerboard. I've also seen it get taped with the fiber-tape used with the backerboard and then mudded once tiled, however it is harder to finish with the tiles in place.

What I would not do is get thinset where the painted surface will be, and I would make sure it is taped if not completely covered by tile. I would use a setting compound for the taping, not ready mix, as it is harder and more durable, and won't mold like readymix will.


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