hardie backer bed adhesive question?

[mjd]

Hi,

Been browsing around the forum and see there is a lot of good info here, just looking for some advice on how best to tile my porch.

The floor is chipboard approx 2m2, no detectable deflection, but is not 100% level or flat. I've bought 300x600 porcalain tiles and am hoping to get a pretty crisp finish.

I bought some 6mm hardie backer boards, they seemed a better option for ironing out the minor deviations and would not cause a big height difference with the hallway.

Now I'm slightly confused as the instructions state to use a non-flexible adhesive to bed the boards. this goes against my understanding to use flexi adhesive on wood based floors?

Normally I do a lot of research first but just went with the shop's suggestion this time and was sold Mapei Keraquick, I ended up reading up on it anyway I reckon I should also use their Latex PLus product with it and have bought some, any issues with that?

I also was sold Mapei Ultracolor plus, is this grout ok for what I am planning?

(Note that the shop thought I was overboarding with ply, I only decided on the hardie backer once I had ripped up the old tiles and saw the uneven floor)

Thanks in advance.

 

[Gazzer]

You will be fine with what you have. You need to glue and screw the boards.

"Fast setting polymer modified flexible S1 adhesive for fixing all types of ceramic, porcelain & glass tiles, mosaics and non-moisture sensitive natural stone to internal and external walls and floors. Suitable for plywood overlaid substrates. Mix with LATEX PLUS for increased flexibility to S2, for tiling to other timber substrates and fixing resin backed glass tiles."

 

[Bubblecraft]

As above & welcome to TF

 

[mjd]

i guess just to clarify, i currently have no adhesive for the backer boards, the keraquick was for the tiles.

So if i were to go out and buy some for the backer should i go flexi or just follow the instructions and have non flexi?

thanks for the quick replies!

 

[Diamond Pool Finishers]

:welcome:to the forum M8 take a look at my web-site by clicking below

 

[Dougs Third Go]

I actually spoke to hardie regarding the non-flexi adhesive, and the technician claimed it was a typo and that flexi adhesive should be used.

 

[mjd]

thought i would just phone hardie technical as well to say what they said. The first person who answered had to "ask their supervisor" the answer came back as use "normal" adhesive for the boards and felxible for the tiles.

 

[mjd]

one other general question, i wanted to have a small grout line so bought 3mm spacers, is there any reason not use them on 300x600 tiles?

 

[Gazzer]

Just use the same "Flexi" adhesive for boards and tiles.

3mm joints is min BS for floors so its all good.

 

[DHTiling]

Is this chipboard onto joists.. ?

 

[charlie1]

I don't think the technical department at hardie have a clue tbh....
they told me that there product was not for over boarding floor boards alone... Ply wood must be laid first!!!

 

[mjd]

Is this chipboard onto joists.. ?

Yes, chipboard onto joists. Floor is pretty stable as it's right next to the exterior wall and there is an access hatch in the floor so it has extra noggins.

I don't think the technical department at hardie have a clue tbh....QUOTE]
got to say, the girl who answered first certainly didn't come across as knowledgable.

 

[beanz]

I assume you're keeping the hatch accessible?