Bathroom wall tile adhesive: Thin-set mortar or OmniGrip glue?

novice10

For my shower wall tile adhesive, should I use Thin-set mortar or OmniGrip glue?

Thanks!

iminaquagmire

Thinset. Mastics are organic compounds that breed mold. There is a whole host of improper ways to do tile showers and few proper ones. Tell us your plan so we can advise further.

Bud Cline

No question about it: Thinset Mortar in all wet areas.

novice10

Sounds like Thin-set is the winner!! Also, if it wasn't clear, since I suggested Thin-set, the shower walls are cement boards (Hardie Backer). I sure this makes a stronger case for Thinset.

A sales person at HomeDepot suggested OmniGrip, but he didn't appear too sure. I'll be returning the OmniGrip glue.

@iminaquagmire - For tiling, I'll be starting horizontally at the middle of the wall. I have a 1"x4" board strip that I'll leveled horizontally and start tiling upwards from the board. Please share pointers if you have any. I'm a little concerned because my shower pan isn't 100% flat, but maybe I'm trying to achieve exact precision where not needed.

Happy New Year!

Bud Cline

Install your 1X4 (ledger board) in a location that will allow for slightly less than one full tile (85%-90% of one single tile) to the tubs surface.

This way all that will remain to be done will be one row of tile. That one row of tile can then be cut to properly meet the tubs surface allowing for a 1/8" gap at the tub. That 1/8" gap can be achieved using 1/8" spacers on the tub. Remember when cutting-in the bottom row to allow for the grout line above that bottom row of tile.

iminaquagmire

Have you installed any of this stuff yet? While backerboard will not rot, it is not waterproof either. Water will migrate either by vapor or liquid behind the tile and as such, whatever the tile substrate is needs to be able to impede that water from reaching the wall cavity. Traditionally, a backerboard shower (I much prefer Durock or Wonderboard over Hardi) will have a moisture barrier behind it, that then drapes into the tub or shower pan. The best moisture barrier for this system would be a 6mil poly installed from bottom to top with the seams overlapped.

If you have the backer up already, I would suggest a surface applied liquid membrane like Redquard or even better, Laticrete's Hydrobarrier or Hydroban before your tile. Another option would be a sheet membrane such as Schluter Kerdi.

Once you get to your tiling, picking the right thinset is the next step. If you want to shop at Home Depot, Versabond is a good middle of the road choice. A ledger is a good way to start laying your tile.

You said that your shower pan isn't flat? What kind of pan is it? Does it have the correct slope all the way around?

We love pictures here if can post them. They make things a lot easier.

novice10

Wow, I didn't think after tiling and grouting water would still get through the cement hardi board. The hardi board is 1/2" thick (didn't go with 1/4").

Below are images of my "work" and shower pan level pics. The shower pan doesn't have adjusters and sits atop cement ground (i'm on the 1st floor of a condo).

I don't think the level is off that much (see pics and share your thoughts). For the first tile row, as previously recommended, I plan on leaving a 1/8" gap between the base of the tile and shower pan for silicone/grouting.

http://img100.imageshack.us/img100/2012/img0419eh.jpg

http://img440.imageshack.us/img440/4717/img0425bj.jpg

http://img35.imageshack.us/img35/1627/img0424l.jpg

http://img850.imageshack.us/img850/2811/img0422pz.jpg

Bud Cline

You'll be fine.

You cannot use 1/4" cement board on walls.

Tile showers are not waterproof. They simply provide an excellent watershed. Water will get through the grout, that's the way it is.

If you did not install a moisture barrier on the studs I would strongly suggest you now apply a liquid waterproofing on the surface of the cement board before you go any further.

novice10

I've been researching Redgard waterproofing, and it appears Redgard doesn't work well with Hardie Backer. In this thread (http://www.johnbridge.com/vbulletin/...t=29633&page=4) I found the following below instructions....

-----------
To get a good bond to HB with RedGard (RG) you need to make a primer coat of RG.

Primer is: 4 parts water, 1 part RG. Wipe down the HB with a wet sponge to get all the dust off the HB. Then apply the primer coat.

Let that dry for 3 hours then apply an undiluted coat of RG.
---------------

The above for Redgard seems hit or miss. I would go for Laticrete's Hydrobarrier or Hydroban but it appears neither Home Depot nor Lowes carries these products.

Any other suggestions?

iminaquagmire

The primer coat does work well but I'm personally not a big fan of redguard for the difficulty building a proper film thickness. Lowes carries Laticrete around me and should be able to order it but I don't know. You could also go with the surface applied sheet membrane like Kerdi. I do know that you can order that at Home Depot.

Bud Cline

novice10,
Most of those comments are coming from people like you that have no idea what they are doing and no experience. RedGard is a waterproofing "film" once dried. Why would you apply it then try to peel it off? That's just plain a stupid thing to do and proves nothing. It is a film, of course it will peel off. Why would anyone try to peel it off?

You should get going with your project and stop believing every little tidbit of rumor you come across. My God, this is beginning to read like a "True Detective Magazine". All fiction.

A primer-coat is a good idea and sanctioned by Custom Building Products but not necessary. It is bunk coming from someone that thinks they have a better idea.

You must make a decision as to whether you are going to listen to experienced installers or non-experienced DIY'ers on a forum. How many forums are you going to for advice on this single subject? The more forums the more confusion.

Do what you want.

fixrite

Novice10...Listen to Bud Cline, he is very experienced and knows what he is talking about. He is a no-nonsense guy who will not lead you astray, but will tell it like it is.