Bathroom floor, pre tile dilemma!!

[clubsport]

Hi, I have previously used this forum and received excellent advice which has been proven in a practical application.

My current dilemma involves assisiting a family member with laying a floor to prepare for ceramic tiles in a bathroom.

The bathroom in a 1960's house has 15mm floorboards which run either side and through the bathroom. I had hoped to take the boards up and lay 25mm external ply as suggested in the floor forum sticky. (I also did this on my own bathroom).

As it seemed more of a task to remove the floorboards to the edge of the bathroom, having searched previous posts and advice given, I was happy to lay 12mm external ply over the existing boards...job is a good 'un etc...

The tiler is insistant that flexible adhesive will suffice over the floorboards or at a push a 6mm layer of ply may be required.

I am not happy with the proposed 6mm and having a banking background, do not feel I am in a position to argue with the professionals

Will it all end in tears in a few months or is 6mm ply and flexible adhesives sufficient?

I would appreciate your thoughts....Cheers

 

[gcol]

You can bend 6mm ply with your fingers over a short area. If you can do this with your fingers, think how much damage you can do with your weight applied on one foot. The main reason for fitting ply is to firm up the floor. If you want a tiling job done with no worry about cracking grout or loosening tiles then you need to use 12mm ply. Bal single part flexible adhesive is a must for tiling onto timber in my opinion.

 

[mattysupra]

I would think about using another tiler.

 

[clubsport]

It is tricky isn't it.....I am one family member and the tiler is another...to further confuse things

As I am clearly a non professional, I tend to analyse and perhaps over engineer my projects, things normally work out well, as I don't cut corners on cost to ensure I do the best job I am able. This is balanced with the satisfaction of the job well done.

I appear to have been over ruled on this one and will have to fit the inadequate 6mm covering,,,if and when the tiles pop off of the "trampoline", clearly the blame will be on the chap who layed the floor (ME )

I am grateful for the responses at least to clarify that there is reasoning behind a method and cost cutting in the short term is clearly not the best way.

Thanks

 

[nellyb]

It all boils down to common sense really. As gcol says, try and bend a piece of 6mm ply and then a piece of 12mm ply....there's no comparison. I always tell my customers to go as thick as possible. 6mm ply is just not adequate for any job like this and personally I wouldn't do it if 6mmm ply was going down.

Flexible adhesives are not some sort of magic potion. They take into account a 'small' amount of vibration or movement, they are not elastic bands!

I wouldn't argue with the family member about it, I'd just go to the timber yard and buy enough 12mm ply to do the job without him knowing

 

[clubsport]

Thaks very much for the responses to my dilemma..

I have now shown this thread to parties concerned and despite the plumber, tiler and electrician all apparently saying 6mm will be fine, I now have the go ahead to fit 12mm over the floorboards

All be it a minor moral victory for common sense, I haven't exactly won as I still have to fit the ply...oh well

Cheers

 

[gcol]

Good news. Don't forget to screw the ply down every 200mm all over the sheet.

 

[clubsport]

Cheers gcol,
Yes I am going out to find some size 8 x 25mm pozi head screws, based on the 15mm flooroard and 12mm ply...every 200mm it is.....Tks again

 

[Moz]

12mm ply sheets , an bal single flex mud/adhesive depending on tile ...

are your joists secure/sound an not requiring noggins an wood preserving .. just a thought , best to do a good/boss substrate from the the off
when your screwing make sure your pipe an cable runs are marked on the ply above
may sound stupid but when your drilling pilots an screws in , can be a nightmare to find that flow pipe