Replies

1. 
   JeffBuck | Nov 28, 2002 09:18am | #1

   GENERALLY........1x with a 3/4 ply layer on top....plus the backer would be enough.....

   1/4 or 1/2... duro or hardi.....up to you.....

   definitely thinset the backer to the ply....then screw......I use roofing nails with no problems.....

   Mesh tape and thinset the seams.....real important step....

   Jeff

   ..............Al-ways look on......the bright......side of life...........

                      .......whistle.....whistle.......whistle........

2. 
   CAGIV | Nov 28, 2002 10:28am | #2

   Basically everything that Jeff said

     It is important to tape and mud the joints first, just make sure not to put to much mud on and create huge high spots.   If you don't want to mud the backer to the floor you can use liquid nails, 1 tube per sheet.  I always try to screw my backer to the joists if I can find them, but most of the tile guys I know shoot it like Jeff with a roofing gun.  Last but not least, use the rough side of the backer board, I don't like hardi back because I can only get it with a smooth surface, don't know if they make it rough.  The rough surface gives you a better adhesion between tile and backer.  For the thickness pick which one best is able to level to your floor with the joining room and take into consideration the amount the tile is going to add.  Pick a combination of ply and backer thickness that gives you the best result.