Loose Floor tiles :( New Floor

[Dumbo]

I think you guys might be right, looking at pics on the web it did look like NMP.

So if the NMP wasn't primed beforehand, would this be the reason for them becoming loose? The builder says it's not down to movement as he screwed the board down really well. Really strange that it's happened in 2 bathrooms on different levels. What would be your advice before the tiles are put down? primer and same brand adhesive or would you suggest something else?

Can you just clarify is your cement board (If that is what it is ) fixed directly to the joists with no floor board underneath or is it fixed to the joists through the floor boards .

 

[Southside691]

The cement board was fitted on top of the existing floorboards in 1 bathroom and the other in the loft has ply below. Cement board glued and screwed down builder tells me.

 

[Waluigi]

The problem with overboarding is that sometimes people do it just to tick the box- overboarded.

Before overboarding the existing floor needs to be checked throughout to see how stable it is. How much deflection and mainly how well screwed down it is. Also when overboarding chipboard, the overhang of the chipboard needs to be checked. Some floors just aren’t suitable for overboarding.

 

[Viceroy]

One side of NMP is shiny now as it's pre-primed

 

[hmtiling]

Were the boards glued at the seams also?

 

[J Sid]

has the adhesive stuck to tiles but not floor or floor and not tiles ?

I've asked this question and had no answer as yet.

if you answer @Southside691 we will be more able to say what's happen.

 

[Southside691]

Sorry guys but I need to take the tiles off before I can tell you that so hopefully soon

 

[J Sid]

thank you @Southside691 when you do that that will give a better idea of the root of the problem, until then it could be 101 different things

 

[Southside691]

Sorry for the delayed reply, but with the lockdown in force, I've had time to have a closer look at this. So it seems that the tile has been fixed to the Hardie board dot and dab style 🙁 So the plan is to remove, clean and prime, dittra mat and then tile. Any recommendations on the adhesive I should use? Porcelain tiles. Thanks