What went wrong with this floor????

[#32]

So... have a problem maybe some of you guys (and girls) might be able to help with.

Laid a new floor in a bathroom.

• Tiles; British Ceramic Studio Conran Matt White 500 x 500
• Hardiebacker 250 substrate; adhesive & mechanically screwed to new 22mm tongue & grove floor boards.
• LARSON Standard Set Flex (white) 20kg mechanically mixed to exactly the correct water ratio. (looked really dry and "sandy" in comparison to the BAL stuff)
• Lash level clips used
• Adhesive spread with a 12mm x 12mm notch trowel

Here is the problem...
Came in to the room this afternoon to finish the wall to floor cuts and break off the lash clips on the floor tiles. As i was walking on the tiles I noticed that one of them sounded "hollow" like it hadn't stuck properly.
So I tried to lift it...
TO my horror it came up with just getting my fingers in the grout line!! Then the next one,,,, then the next one,,,, then the next one.... you get the picture.

I pulled up all the tiles, ONLY THE LAST COUPLE OF TILES SOUNDED SOLID, and wouldnt come up. These were laid with a different adhesive as I ran out of LARSONS so used BAL MAX FLEX standard set that I had a bit of. To be fair I thought I should have a go at getting one of the BAL laid tiles up so used a crowbar, which managed to lift the tile without breaking but a lot more pressure was required, so I left the last couple BAL laid tiles down (and covered them, they didnt turn blue).

Interestingly the cut tile that I laid, which I applied adhesive to the back of the tile only and not the floor also came up easily but all the adhesive had bonded to the tile, and not the floor? The opposite to all the other tiles?

Im not one to blame "the tools", and it is probably my error so...

Is it #

1. Did the LASH level clips lift the tiles off the adhesive, I pushed them real tight?
2. Was a 12mm notch trowel too large? Should I of used a 10mm?
3. Is the reason the fact that I didn't back butter each of the tiles before laying (thought that the flat surface would of been suitable to not do this)?
4. Did I not apply enough pressure when laying the tile (did use all my weight on the tile)
5. Did I walk on the floor too soon? LARSON std set says set time is 24hrs, I walked on it in 22hrs, however that doesn't explain the 1st tile that I laid as that would of been over 24hrs (yes I am slow)?
6. Was the room too cold for the adhesive to dry properly? Est. 7 degrees over night with no heating on in the house?

So after spending the afternoon scraping all the tile adhesive off the floor (the 1 tile laid with BAL adhesive was much harder to remove off the floor), tomorrow I will go back to re-lay the tiles as the backs of them are clean as you like, with no adhesive stuck to them.

As a small amount of adhesive remains on the floor that I couldnt get up should I coat the floor in BAL primer first? Or is that un-necessary?

I have purchased a bag of BAL Rapid Set Flex to re-do the job. So hopefully this, with some advise as to my errors on the above should result in a nice white tiled floor tomorrow evening!

Sorry was a bit long, dont worry im not charging someone for this job its my house!...

 

[CJ]

This is why I always prime Hardibacker.

How old was the cement?

 

[Flintstone]

Hello,
The Larsen adhesive is pretty poor, that certainly won't help Matters,but, you have hardly any contact between tiles and floor.
Did you prime the floor?
You should back butter the tiles, and with the 12mm trowel you should get decent coverage.

 

[One Day]

My guess would be this:
Ceramic tile so absorbs water very quickly from adhesive.
Hardibacker (not primed?) so absorbs water very quickly from adhesive.
Poor quality adhesive (it is Larsen and it is poor imo) mixed too dry.
No back skimming or pushing/twisting into adhesive.

Factors combined and you have a very poor weak bond.

 

[J Sid]

as above

 

[#32]

thanks people.

I read on the Hardiebacker installation that no primer was needed? OK I now know to prime the boards, im assuming with just a BAL primer?

The LARSONS was about 4 months in my garage, and who knows how long at the tile giant store? (someone did mention on this site before the larsen stuff is rubbish)

Twisting the tile seamed hard given its 500 x 500, is pushing with my body weight not acceptable?

Should I use a 12mm trowel or a 10mm when I attempt to re-lay tomorrow? I will skim back butter each tile too.

I assume the LASH level clips dont cause any problems for anyone then?

 

[Dan]

Doesn't look like you've pressed on the tiles much at all for the adhesive to key. Those ribs of adhesive still look incredibly straight.

You're meant to push down and twist the tile into place so you squish the adhesive I to a solid rather than leaving the tile resting on ribs of adhesive. You need 100% coverage. I'd perhaps leave the lash clips out, they will give you the impression the tile is fixed well when in fact it may need more adhesive under it.

Somebody skilled would be able to work it out as they drop the tile but somebody not so would leave ribs like that.

 

[Flintstone]

12mm trowel, no less, if you mix right and you prime the floor and back skim, you shouldn't have any problems. Not too stiff a mixture, lift a tile once you have stuck it to see what's happening and if it's doing what you think it's doing!

 

[Andy Allen]

TBH the only adhesive I will only use on a wooden substrate (over boarded) is bal single part fast flex....and bal wide joint grout with GT1 admix......a combination I have used for years with never any problems.

 

[Old Mod]

It's a perfect example of why you need to 'burn' the adhesive into both surfaces.
Where you've troweled the floor, the tile has come up clean, and where you've troweled the tile, the floor is clean.
So if you'd have troweled both, then there'd of been less chance of a failure.
Still no guarantee tho, as your adhesive mix is clearly too dry.
Twisting tiles is never going to achieve a solid bed, and frankly it's impractical, you need to move the tile perpendicular to the ribs of the adhesive on the floor, and the wider the notch, the more you need to move it. And when you start using larger formats this can prove difficult.

 

[Cris]

Last lot of British ceramics I layed were more like chalk than ceramic. Very absorbant and sucks moisture out of adhesive way to quick so added more water than normal to mix and back buttering was essential

 

[LM]

You've done a multitude of things wrong I'm afraid,
No primer
Used Larson 'adhesive'
No burning or keying of both surfaces
'Adhesive' mixed to tight
Wrong bedding in of tile
Some people in the past have claimed that this game isn't a trade, but a lot can go wrong without learning it correctly ehh
I think you've got the answers you'll need to get this situation resolved, good luck with it

 

[tommyzooom]

Larsen "trade" adhesive was your first mistake, as it is sh1te

 

[#32]

Thank you people. I will try again today with all the helpful comments.

 

[#32]

One other question if I may.
I was going to lay floor tiles.
Then once gone off cover them.
Then move on to putting my final row of cut tiles on the wall (to meet new floor tile).
Then I was going to grout the walls.
Then grout the floor as I leave the room.
Is this right? Ie walking on the floor tiles prior to grout?
Maybe it's a daft question, I don't know?