What thin-set to use for Hardiebacker board seams?

[Ukrop]

Hi everybody!

I know, I should ask it at johnbridge.com forum but they don't register new members for some reason...

Anyway. I'm moving slowly on my first bathroom project And new questions are popping out. They sound silly for professionals but I'm newbie

The question:
what thin-set should I use on Hardiebacker 500 cement board seams? I put them on bathtub walls. I got special mesh tape and I bought MAPEI 50-lbs Standard Tile Mortar with Polymer (we'll go with ceramic tiles on bathtub walls):
https://www.lowes.ca/products/view.aspx?sku=9625191

May I use this thin-set?

Thanks!

 

[Jadnashua]

Yes, you can use that thinset and you definitely don't want to use drywall compound! Keep in mind, that tiling board seams are not like dealing with drywall...it doesn't need to look pretty and the tape doesn't need to be embedded fully, it will be when you add the thinset and tile. HardieBacker is particularly thirsty...liberally wipe it down with a wet sponge prior to adding thinset, or it will suck all of the moisture out of it, making your thinset much drier and harder to do anything with. IT's not too wet unless there is liquid water on it...damp is fine, just not dripping wet. SOme even go the to extreme of using a garden sprayer to wet it down then wait a bit for the liquid to either absorb or dry off. It's almost impossible to get it too wet with a sponge.

Now, if you're not going to be adding a topical waterproofing to the walls, and have a moisture barrier behind the Hardie, you do NOT have do tape and seam the walls, let it cure, then tile...you can add the tape AS you are tiling. This is actually easier, since otherwise, it's easy to make a speedbump. On a wall with drywall, you need a little hump there to hide the seam, on a tiled wall, you do not want that because it's going to be covered by that solid tile that won't bend.

You might have been caught in a time when the John Bridge website was doing some maintenance...try again to register.

 

[Sponsor]

 

[Ukrop]

Thanks!

Yes, you can use that thinset and you definitely don't want to use drywall compound! Keep in mind, that tiling board seams are not like dealing with drywall...it doesn't need to look pretty and the tape doesn't need to be embedded fully, it will be when you add the thinset and tile. HardieBacker is particularly thirsty...liberally wipe it down with a wet sponge prior to adding thinset, or it will suck all of the moisture out of it, making your thinset much drier and harder to do anything with. IT's not too wet unless there is liquid water on it...damp is fine, just not dripping wet. SOme even go the to extreme of using a garden sprayer to wet it down then wait a bit for the liquid to either absorb or dry off. It's almost impossible to get it too wet with a sponge.

Now, if you're not going to be adding a topical waterproofing to the walls, and have a moisture barrier behind the Hardie, you do NOT have do tape and seam the walls, let it cure, then tile...you can add the tape AS you are tiling. This is actually easier, since otherwise, it's easy to make a speedbump. On a wall with drywall, you need a little hump there to hide the seam, on a tiled wall, you do not want that because it's going to be covered by that solid tile that won't bend.

You might have been caught in a time when the John Bridge website was doing some maintenance...try again to register.