thinset ?

Hey,

Just got my CBU up ( 15# felt behind) Question What is the difference betweem gray unmodified thinset and the white thin. Can the gray stuff be used to tape my seams? and does either make a difference on either Hardi or Wonder?

 

A modified thinset is recommended. From a bag, not premix.

 

what if i used an unmodified, would that be un salvagable?

 

The reason I mentioned modified is the tile will grab the walls a bit sooner than with unmodified, only for the comvenience of the install. If the tile is set already don't worry wbout it.

 

Use the modifed thinset. The actual question as to whether or not there is a difference between gray and white unmodifed thinset, yes, the difference is white thinset contains a purer portland cement and therfore has a higher shear bond strength, but once the unmodifed is mixed with liquid additive, the difference in quality becomes negligable. As for backer seams, always tape with modified thinset. Either go back to where you purchased the unmodifed and get the liquid additive (use only that, and no water) or return the unmodified and get modified thinset. Use no premixed products at all. Powerdered products only, mixed with the appropriate liquid, be it additive or water. If you used hardibacker, make sure you sponge down the boards before setting any tile.

 

Yes, either color will work fine for taping the seams, do this while tiling to keep from having humps to deal with.