[Jim W]

I am adding a 1000 sq ft addition and have done most of it myself. I decided to have "pro's" do the sheetrock and they have done a great job to this point.
However, when they installed the wonderboard in the downstairs shower (tub surround) they screwed the wonderboard up with the smooth side out. The whole thing is all taped and sanded (except for the Wonderboard seams which I will mortar when I tile).
* Can I morter the tiles to this surface?
* Should I rough up the smooth surface so the tiles adhere better?
* Should I take the wonderboard down and do it over?

Thanks,
Jim W

 

[canadaclub]

If the smoother side is showing, why not just adhere the tile with mastic instead of thinset? Personally, I think the thinset works on both sides, but haven't tried it.

 

[rjniles]

If the smoother side is showing, why not just adhere the tile with mastic instead of thinset? Personally, I think the thinset works on both sides, but haven't tried it.

Do not use mastic in the shower! It is not suitable for a wet location. I would use the thin set on the smooth side and not worry about it. Try a little test, uit some thinset on a scrap of wonderboard smooth side and install a tile. Wait a day and try to get it off.

 

[canadaclub]

yep, great idea.

 

[Jim W]

Thanks

I already knew about the mastic - it's definatly not for wet locations.

Roughing up the smooth surface isn't going to be too tough with a wire cup brush on my small angle grinder. Mortar need something to bite into and the wonderboard is really smooth.

Thanks for the response