Wonder board and Redgard?

[EightFingers]

Do you install the Wonderboard smooth side or rough side out when using Redgard? I will be using a modified thin set mortar in this application.
I made the mistake of Googling and it’s 50/50 with nothing definite.
You’d think that would be settled by now. 
What I’ve seen was use the smooth side for mastic and the rough side for mortar, but those listings don’t mention Redgard.

Uggggg..

Anyone here have an opinion?

[Woodenfish]

I would just go ahead and install the board smooth side out. Once you apply Redgard everything is going to be smooth anyway so it doesn’t matter much at all. I like to caulk my corners with SASHCO BIG STRETCH caulk before applying the Redgard. I then apply two coats of the Redgard.

[Roly]

I would just go ahead and install the board smooth side out. Once you apply Redgard everything is going to be smooth anyway so it doesn’t matter much at all. I like to caulk my corners with SASHCO BIG STRETCH caulk before applying the Redgard. I then apply two coats of the Redgard.

+1 on smooth side out (easier to apply to) .   Except I use thinset and embedded mesh in corners, then 2 coats of RedGuard with the first coat thinned a little.   Roly

[EightFingers]

Thanks, smooth side out it will be!

[Snipe Hunter]

I don't like working with Wonderboard or Hardiebacker. Only used it once and thought it was a pain. IMHO, Durock is easier to work with, cut etc. It's a little messier but tile work is messy anyway. It's also difficult to sink the screws flush into it. And Durock has the recessed long edge making seam mesh easier to keep flush with the face of the board. Just my 2 cents.

It looks easier but looks can be deceiving.