Please Help !!!!!!!

[The D]

this type of thing is the reason i try to avoid tiling on to ply at any thickness. you could have used a 12mm baker board and there would have been no issue with the height and would have been a more suitable sub-straight to tile on to.

 

[davy_G]

Where is the debonding occuring? Is is along specific lines, like at the edges of the ply sheeets? Or at the boundary from one floor type to another, or into a new extension.

If so it could be settlement or movement of the building, inwhich case movement or expansion joints should/could have been fitted? What area of tiles is involved as there should be expansion joints regularly added.

I did a bathroom floor in an old house, plyed with 12mm exterior. 2 years on after a wet summer and no heat on in the house and then the heat on in the autumn the old beams moved and caused the whole floor to drop. :yikes:Tiles cracked where two ply sheets met.
All fixed with Ardex addy. Took a day to cut out the grout, lift the tiles, remove the addy from the ply (that took the longest). Insert an expansion joint and retile and grout. It worked as no more problems but if id thought and inserted it in the first place i wouldnt have the slightly smaller cut tile against the expansion joint. I did the work for free, although the woman of the house was happy to pay if i wanted.

 

[andy-p]

Thanks for the replies, if my memory serves me correctly the tiler was a bit of a stickler to the rules, i not only got the living room floor done but got my hallway floor done as well, if 18mm ply had been put down i would not have been able to open my front door as this would have brought my existing floor up 35mm and too high for the door, i remember the tiler taking about a day to glue and screw down my floorboards as they were a bit of a mess and lay the plywood screwed at 6" Centres the top and sides were sealed with Bal Bond, he used a 10mm Serator when laying the floor, can someone tell me after 17 months of no problems whatsoever why is this happening now, it always seems an easy excuse saying ply to thin as this reason is sited on many sites from 6mm to 9mm but 12mm ply, i mean who can really buid there floor up by an additional 35mm

I would have used a 16 or 20mm trowel on tiles that size , though i dont know if this caused the problem..

 

[mikethetile]

something not right here

10mm serrator................how many clients know what size notch your using

 

[user123]

something not right here

10mm serrator................how many clients know what size notch your using

My thoughts exactly, even before the serrator question came up....Guest, I read through all the posts, what an astounding memory on what was used and how after how many months?.... ....sounds to me as if you had done this job yourself and are now wondering what went wrong? :whistling:

 

[Pebbs]

This is better than watching a series of Poirot...come out with your hands up! and confess all!

Pebbs

 

[andy8758]

I understand the value of having a forum where anyone can post a query about tiling, and get lots of informed advice, but...

- anyone can log on anonymously as a guest

- with such anonymity they can state, challenge, and argue without recourse

- and without pictures, we have to assume that the query written is accurate

Noble, maybe. But this post seems to be tying everyone up in knots, and I agree with the suspicions aired - could it be the poster tiled this themselves, and is distorting the information about how this was done "professionally" and should never have gone wrong?

Perhaps this "guest" posting status needs to be revisited?

 

[Pebbs]

Mike aka Poirot and Gisele aka Miss Marple, were soon on the case....theres no pulling the wool over the eyes of these two.

 

[macten]

If I had to tile 12mm ply I would have used a 2-part.
But I wouldn't as I would use cement board.

 

[andy-p]

If I had to tile 12mm ply I would have used a 2-part
But I wouldn't as I would use cement board.

Is 10mm cement board more rigid than 12mm ply ?? and well spotted Mike ...

 

[Scott]

Is 10mm cement board more rigid than 12mm ply ?? and well spotted Mike ...

No, but its better to tile onto but wont take out any deflection.

 

[mikethetile]

No, but its better to tile onto but wont take out any deflection.

spot on scott

 

[TheTiler]

Sounds like movement in the floor. Likely to be expansion in the hot summer months we've had drying out your timber substrate. Did he leave 5-6mm expansion gaps (filled using silicone NOT grout) around the perimeter of the floor and use an expansion strip over necessary lengths in the floor area? Very important to do this when using large format tiles on timber (I've seen it go wrong in one of my jobs, and I've learned from it).

 

[Unregistered]

The answer.....

A 2-Part flexible adhesives should be used when fixing 600x600mm Porcelain onto timber. The mass size and limited amount of porosity on a 600x600mm Porcelain means you need a chemical bond (single part adhesive) rather than a mecanical bond (where the adhesive soaks into the back of the tile).

Always remember -

Single Part is good enough for a single solution (either 600x600mm onto cement, or max 400x400mm onto timber)

Two Part is good enough for Two solutions (600x600mm onto timber)