Would 12mm plyboard be right for this?

[Averroes]

Hi guys, have been reading many threads over the last few days and have gathered some tips and advice given by members to others newbies such as myself.

Rather ironic that last year I put in some floor tiles in a basement kitchen of mine letting my instincts leading the way and it turns out that most of my methods were similar to what you guys have advocated.

However that was a pretty straight forward floor and now I am faced with a much tougher task.

I have a floor that is floor boarded at the moment but is done in three parts. The floor is level however but floor boards have been put in three parts so there is a little difference between them.

The problem i am really faced with is that the floor is to immitate the shape of my ceiling which is a bespoke curved shape. The inner curve is to be tiled with white porceline tiles 1/4 meter square coverage per tile and the outer curve to be carpeted.

To do this correctly am I right in saying i need to lay down 12 mm ply throughout to get an even floor as possible and furthermore would i need to skreed the floor as it is prior to laying the ply?

I have many other questions but would prefer to break it down step by step so you guys can give me better advice

cheers

 

[GazTech]

If you can level the difference in the boards prior to any overlay, then this makes tiling much easier. I would overlay then with backerboard as opposed to ply ( more stable ), then depending on how much you wan't the floor to be raised answers the question of which adhesive and grout should be used.....Gaz

 

[Fekin]

Aye backerboards all the way for me

 

[Averroes]

hmm ive heard of underlay, whats overlay, sorry to sound dumb

so i need to "overlay", then put in backerboards and then maybe skreed with some form of leveling compound?

Also what benefits do backerboards have over ply and are they cheaper or more expensive?

 

[GazTech]

hmm ive heard of underlay, whats overlay, sorry to sound dumb

so i need to "overlay", then put in backerboards and then maybe skreed with some form of leveling compound?

Also what benefits do backerboards have over ply and are they cheaper or more expensive?

To 'overlay' is to screw down ply or backerboard over existing boards. Then depending on type of 'overlay', will give you choices of adhesives and grout......gaz

 

[Averroes]

o lol i guess i misread your previous post into thinking overlay was something additional.

Regarding backerboards, what are the advantages of using these over ply and what is the cost difference and also do i not skreed prior to 'overlay'

 

[Fekin]

Backerboards are thinner and cannot be affected by water, like ply can be.

 

[Averroes]

Fekin, ive been told to get 12mm ply because of its properties as being thicker and heavier. I.e. the thicker and heavier it is, the less play there will be, have I been told correctly or are these fibs.

Also are backerboards more expensive compared to ply?

 

[DHTiling]

The thicker the ply the better it will for deflection...( within reason)....ply will only help to a certain degree....but yes it will help...........backerboards are ideal if the substrate is solid to start with and will handle moisture better than ply....

Also backer boards can be more expensive but are worth it for long term effectivness............

 

[Averroes]

Dave thanks for the reply matey. The problem is that I have a floor which is floorboarded. It looks even enough but to eliminate any possibility of play i wanted to apply some form of 'overlay'. Now yes the properties of backerboards sound interesting but the thickness is making me a little reluctant. plus the whole floor is not to be tiled, about 1 third of it is only

 

[DHTiling]

Make sure the floor boards are well fixed ( screwed down)....then ply over with 12mm ply and tile using BAL fastflex and BAL wide joint grout with GT1 admix or similar products........this should give you enough height for the carpet to match the tiles floor in height.........

Backerboards are ideal for bathrooms but if you need the height for the carpet then ply is the way to go...........although backer board does come in 12mm as well.........

Good luck.........

 

[Averroes]

Dave shall i not skreed over the floorboards with anything first and then ply? or have i been misguided here

someone said i need to skreed over with something to make sure the ply sits properly even though the floorboarded floor may seem even

 

[Averroes]

Any thoughts on this anyone?

 

[grumpygrouter]

You only really need to level the sub floor if it is undulating or out of "flat". Self Levelling Compound is what is normally used for this. The choice is yours and it depends on how "Flat" you want you sub floor. The flatter the better in my opinion, but if you have not used SLC before, it is by no means straight forward.

Arditex by Ardex is ideal for this though it does stink a bit! it is a 2 part latex based leveling solution. They also do a low odour version but I have never used this.

 

[Averroes]

Lol love the username Grumpy and thanks for the reply.

You see regarding the floor being flat, yes it is flat but because the building is built on a slope it isnt exactly centre level. The other thing is, since the floor boards are in the sections I am a little concerned whether the change between each bit has any effect on the ply i.e. will a little 2 mm kink underneath 12mm ply have any major effect.