Help!: Tile Giant Advice.....

[kevg]

some of the floors I'll be tiling in my new home are ply. After a trip to tile Giant today I was advised that I wont need backer board to lay on top of the ply, just use mapei proflex then tile on top.

I'm certainly not an expert and from what I have been reading and the advise I got from this forum, it made me pretty nervous as I thought I knew what I needed.

I had planned to get some hardie backer and my adhesive would be a mix of keraflex with latext plus.

Is there more than one way to tile onto ply ? Have I been given the correct advice but can choose either the tile giant way or the way I was planning myself ?

[Dave]

Depends on the ply and where this ply is laid etc,

[deanotile]

BS 5385 Code of practice 3.2.4.2
The use of sheets and boards that are subject to movement from changes in moisture content, e.g. wood-based materials such as plywood, chipboard, wood particle boards, etc. should be avoided if at all possible. If such boards have to be used they should be restricted to small areas and tiles should not bridge joints between boards. It is good practice to seal all exposed edges and the backs, but not the faces, of such boards with a suitable sealer to prevent distortion by atmospheric humidity changes. Care should be taken to ensure such boards are not installed in a condition where their moisture content is higher than the ambient equilibrium moisture content once the tiled installation is in use. Failure to observe this can lead to subsequent warping and distortion of the boards with consequent cracking and delamination of the tiling.

[kilty55]

hi kev,it wouldnt be my choice to tile onto ply in a bathroom i would have gone the cement board route,with keraquik

if you feel youd be safer going the route you wanted to do the follow your instincts as i would choose the same way

[Dave]

Dean.. 10mins to 1 am .. FFS bs5385 this time on the morning.... now that is TF dedication for ya.

[jay]

use 6mm cement sheet screwed and glued and stagger your joints

[deanotile]

am i sad m8 (do not answer that)

[kevg]

Depends on the ply and where this ply is laid etc,

The 3 upstairs rooms are 1x bathroom and 2x en-suites.

BS Code of practice 3.2.4.2
The use of sheets and boards that are subject to movement from changes in moisture content, e.g. wood-based materials such as plywood, chipboard, wood particle boards, etc. should be avoided if at all possible. If such boards have to be used they should be restricted to small areas and tiles should not bridge joints between boards. It is good practice to seal all exposed edges and the backs, but not the faces, of such boards with a suitable sealer to prevent distortion by atmospheric humidity changes. Care should be taken to ensure such boards are not installed in a condition where their moisture content is higher than the ambient equilibrium moisture content once the tiled installation is in use. Failure to observe this can lead to subsequent warping and distortion of the boards with consequent cracking and delamination of the tiling.

I'm a simpleton lol. I think that means I should use a backer board ? *insert embarassed smilie here lol*

hi kev,it wouldnt be my choice to tile onto ply in a bathroom i would have gone the cement board route,with keraquik

if you feel youd be safer going the route you wanted to do the follow your instincts as i would choose the same way

That's what I was thinking, but these guys know a hell of a lot more than me, it threw me off guard though. Sometimes when you think what your doing is correct, all it takes if for different advice to put me back to the start.

[kevg]

use 6mm cement sheet screwed and glued and stagger your joints

marmox or hardiebacker be ok ?

[Dave]

Deanotile is ya man here.. 1 am in the morns is deano's territoriality.

[kevg]

Deanotile is ya man here.. 1 am in the morns is deano's territoriality.

Man after my own heart !

Now all I need is his advice hehe.

[deanotile]

i like Hardi but as long as you do not tile directly on to the ply i am happy

[Daz]

I gotta agree with Deano

[Dave]

i like Hardi but as long as you do not tile directly on to the ply i am happy

Aww, now you being shy!..

[Scott]

What size area are the floors? Is the ply the main substrate or has the ply been laid over an existing floor?

[kevg]

What size area are the floors? Is the ply the main substrate or has the ply been laid over an existing floor?

I've just been back to the house, it actually looks like its chipboard thats sitting down on top of possibly floor boards ?

IMG_0020.JPG

Room sizes are

En-suite 1 = 2.09m x 1.73m
En-suite 2 = 2.60m x 1.73m
Bathroom = 2.25m x 2.34m

[Scott]

Yes thats chipboard alright and its the older stuff too. Has it got wet anywhere that you can see? Normally outside the sower tray and down the side of the bath, under the basin pedestal and round the bottom of the toilet.
It swells when its wet and goes crumble, the same as weetabix.

It a bit of a mare to change it but it can be done, however if its not got wet then you can overboard it with either a cement backer board or ply. The choice of materil will depend on the amount of deflection in the floors. If there is deflection then you have the option of either overboarding with 15mm minimum ply or removing the chipboard and replacing it with a thicker ply. 18mm upwards.

The backer board option is only really going to work if the floors have no movement. However you can still add them over the ply to provide a more suitable surface for tiling. Of course all that will mean raising the height of the floor somewhat.

[leec]

carrying on with NMP is it essential that its primed before being tiled over??

[whitebeam]

Not on cement board

[leec]

ta whitebeam