Hardi Backer Board for floor tile

[MountainDon]

Has anyone used Hardi Backer Board as their ceramic floor tile underlayment?

Hardi's instructions include taping and jointing the joints between their panels, using fiberglass alkali resistant tape. Did you do that? Did the floor work out anyways?

[MikeT]

Don:

We used the Hardi product as a base for our slate floor.  Pulled up the linoleum, used thinset on the backerboard and also used roofing nails (instead of the screws that Hardi wanted you to use).  For tape, I had leftover fiberglass tape from a different project and used that. 

The guys at the big tile store here in Portland (as opposed to HD) recommended not scrimping on the thinset and get a good quality product.  They said the marginal difference in cost pales to the superior quality of the better stuff.

That's what I got....

[MountainDon]

You used thinset to cement the backerboard down, as well as nailing, then taped and jointed, then thinset and set the tile on top. Right?   

[glenn kangiser]

I did the same in our bathroom at the other place about 15 years ago.  I put in marble.  It was 1/2 backer board over 2 layers 1x3 t&g floor and sub floor - never a problem and I probably didn't follow details that well.  I also did the tub surround with it - again -no problem - 1" square ceramic tile there.

[MountainDon]

.... I probably didn't follow details that well....

[glenn kangiser]

Still working.

[MikeT]

Yes, Don.  That is the stuff I did and in that order.  8 weeks ago and still working....

[PEG688]

Thats what our floor guys do just like Mike T's post , the roofing nail really are clamps , you could ( no one does and neither shoud you Mr Anal Renetive felter guy  ) remove the nails and fill  the holes. Like I said they really are clamps.

If , and I doubt you do , you have any subfloor joints that are NOT T&G and the  sub-floor flex's due to that you should  gusset the joints that are like that.  That condition is 'mostly' found on remodeling jobs or old places that have been repaired or poorly built from the get go. 

[MountainDon]

... remove the nails and fill  the holes.

   No Way! Once the nails go in, that's it.

If , and I doubt you do , you have any subfloor joints that are NOT T&G ........

All T&G. Yep.   

[Okie_Bob]

Call me paranoid but, I used the recommened screws instead of nails. I just felt the little added price was justified if it helped keep the
Hardi-BackerBoard from ever moving. So far so good. I'm a Hardi fanatic though.
Okie Bob

[Mandres]

Has anyone used Hardi Backer Board as their ceramic floor tile underlayment?

Hardi's instructions include taping and jointing the joints between their panels, using fiberglass alkali resistant tape. Did you do that? Did the floor work out anyways?

What is the 'jointing' part of the "taping and jointing" process?  Are you spreading a thin layer of thinset over the tape like you would with drywall mud? 

[MountainDon]

That's basically it.