When taping seams , do you guys tape and set tile at the same time, or let the thinset dry on the seams first?
Taping backer board seams
- Thread starter Don Monfils
- Start date
Help Support Flooring Forum - DIY & Professional:
Always tape as you go with the tile.
If you tape ahead of time and allow it to dry you'll have teeters you won't want to deal with.
Bud, whats a teeter?
The reason I ask we installed 55 sheets of Hardie and taped as we went.
Another tile guy came there to do a shower and he said I should tape while setting the tile,otherwise you get a bump where the tape and mud is(I think that's the teeter Bud is speaking of). He is an excellent installer and it does make sense. I remember trying that before and kept lifting the tape, maybee I just need to be more aware of which direction the tape is going and comb the thinset along the length of the tape.
This other tile guy also said he never uses thinset under backer board he uses urethene construction adhesive. I think I will stick with thinset.
I also asked him about applying the thinset with the flat side of the trowel to burn it in b/4 combing it with the notches and he said he doesn't do that either.
I always do that.
Another tile guy came there to do a shower and he said I should tape while setting the tile,otherwise you get a bump where the tape and mud is(I think that's the teeter Bud is speaking of). He is an excellent installer and it does make sense. I remember trying that before and kept lifting the tape, maybee I just need to be more aware of which direction the tape is going and comb the thinset along the length of the tape.
This other tile guy also said he never uses thinset under backer board he uses urethene construction adhesive. I think I will stick with thinset.
I also asked him about applying the thinset with the flat side of the trowel to burn it in b/4 combing it with the notches and he said he doesn't do that either.
I always do that.
Polestretch
Well-Known Member
Don, My old boss used urethane construction adhesive under his Hardie, and we nothing but trouble about 5 years out. we also apply the thinset with the flat part of the trowel before the notched side. That is in the instructions!
ALL cement board makers recommend the use of thinset under their boards.
NO cement board maker recommends construction adhesive.
Very bad idea!
Construction adhesive is generally applied in (strings) and will over time become super hard. The voids where no adhesive string exists is an air gap and air gaps equal movement.
The use of thinset is to provide 100% fill under the boards, it is not used to adhere the boards to the substrate.
Exactly!
When taping joints ahead of tiling (as you tile), long seams do not need to receive tape all at once. Apply just enough tape to meet the row(s) requirements (layout requirement) so you aren't crawling around all over the tape and screwing it up constantly.
