Mastic [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


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08-29-2016, 12:46 PM
So, I made the dreaded mistake of trusting those at Lowes for advice and bought Type ! Mastic as my adhesive. So far I have only done the bathroom floors, both bathrooms will have non-tile floors-one is a tub/shower combo and one is a fiberglass type shower surround. In the bath shower combo I have a window and was planning to tile the surround and up to chair rail height around the room. There won't be excessive mousiture but these bathrooms will be used daily. Neither have been grouted. I tiled the first one on Saturday (2 days ago) and the second one Sunday (yesterday). Do I need to try to pull them up and wash the mastic off and start again with thin set or will the bathroom floors be okay and just switch to thinset moving forward? Please, I hope it is the later. This was my first time tiling and it looks so pretty...i was soooo proud!!!

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08-29-2016, 12:56 PM
You can gamble and see if it holds up but I wouldn't take that chance. The sooner you take it up the easier it will be. Odds are its still wet underneath.

08-29-2016, 12:56 PM
Personally...I wouldn't sweat it. I'm just a DIY'er...but outside of a flood I don't think your bathroom floor would get wet enough to be a problem. I have a friend who's done many floors, including bathroom and showers with mastic and has never had a problem. I'd just pick up a bag of thinset and start using that moving forward.

Just my two cents...

08-29-2016, 01:11 PM
Welcome, Karma. :)

...both bathrooms will have non-tile floors... If the only part of the rooms that are tiled with the mastic is the dry area wainscot, I wouldn't worry about it at all.

What am I missing?

08-29-2016, 02:36 PM
What I meant to say was that the bottom of both tub/shower and stand up shower will not be tiled. The remaining bathroom floor is what I have already tiled. I already bought thinset to use on tub/shower surround but hoping you think it's okay to leave it on the bathroom floor. Thanks!!!

08-29-2016, 05:33 PM
Over what subfloor and substrate did you tile, Karma? With what type and size tiles?

08-29-2016, 08:13 PM
Over osb which we laid Durock on top of. Ceramic 6.5 by 6.5, 1/4 inch in one bathroom. The other bathroom was sheets of mosaic also osb

08-29-2016, 08:52 PM
If your joist structure is adequate and if your subflooring is adequate for the joist spacing, and if you've installed the Durock per the manufacturer's instructions, your Type 1 organic adhesive meets all the manufacturers' requirements for your installation.

While it's not what we'd (TYW) recommend as an installation method, I'd leave it alone until it fails if it's gonna. May last a long time.

My opinion; worth price charged.

08-29-2016, 09:07 PM
Thank you CX. The joists and subfloor have all just been totally replaced and I think we r good on our Durock install.

Okay next question order to adequately prep my tub/shower surround we r planning to thin set, mesh tape for cement board on joints, etc then use the mapei aquadefense, does this sound appropriate? An additional challenge is a window in the long side of the tub wall. How do recommend we approach that in addition to what I've mentioned. Thanks!!!

Houston Remodeler
08-29-2016, 09:45 PM

The waterproofing for the walls sounds good. Be sure to get the right thickness on the AD. Use a wet film gauge for best results.

For the window, bond the AD to the window frame. The silicone caulk the gap between the tiles and the window frame. You do have a vinyl or metal window frame, right ?

08-30-2016, 02:51 AM
Thanks Paul, yes we just replaced with a new vinyl window.

I'm sorry but I don't know what a wet film gauge is, where do I get that? I read the package and was unsure about the 20mm (I think that's what it was) max thickness-that certainly is difficult to judge!!

Houston Remodeler
08-30-2016, 06:18 AM
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