Bug and Defect Report Email Address

NOTICE: Thank you for your continued patience with the persistent bugs affecting the JLC Online Forums. We've setup a special email address for reporting issues and defects. Reports will go directly to the assigned IT team members. Please include screenshots if you can. There were some widespread issues over the past weekend which have been resolved. However, we know that various error pop-ups are still occurring during post composition and at other times. Thanks again. Here's the email address:
See more
See less

Durock cementboard seams

  • Filter
  • Time
  • Show
Clear All
new posts

  • Durock cementboard seams

    I am in the process of finishing up my complete bathroom gutting and reconstruction and have just installed Durock cement board everywhere that can possibly be exposed to water. I am ready to tile.

    Question: What do I do to the seams of the Durock cement board? The Durock was purchased in 3x5 sheets from HD and the employee/professional told me to just use thinset. Is this correct?

    Thanks in advance.

  • #2
    Re: Durock cementboard seams

    Use thinset mortar with an alkali-resistent fiberglass mesh tape, and install the tape at the time the tiles are being installed--spread the thinset for the tile, press in the tape, and install the tiles. this method results in the lowest , smoothest surface profile. Filling them ahead of time, since backer boards do not have a tapered edge, usually results in a slight hump.


    • #3
      Re: Durock cementboard seams

      MB, if you press in the tape after combing out the thinset, won't that give you an inconsistent layer of mortar there under the tile? Or maybe interfere with the full adhesion of the tile?


      • #4
        Re: Durock cementboard seams

        The tape is actually open-mesh fiberglass tape that thinset passes through readily.

        I used to apply the tape first, then spread the thinset, but the teeth on the trowel tend to snag on the mesh, so I place the mesh after spreading.

        It has never seemed to interfere with the adhesive bond in the 20 years I have been doing it.