Garden tile lifting !? - Tile Advice

[Stevelondonuk]

Hi all. So I have just finished laying my 600 x 600 x 20 mil porcelain tiles in the back garden over a type one base. One of the tiles I was running short on cement and so I did a sort of dot and dab thing which didn't work in the slightest and came loose the next day. There was still quite a bit of cement there, but just not enough for a full bed.

I then took it up, dug up some of the existing cement and filled up the voids and topped up the rest and relay the slab. The next day, it was loose again.

I then dug out all of the cement (which was quite a dry mix) And scraped as much off of the back of the tile as I could, I then filled up with a new batch of slightly wetter mix, re-primed the back of the slab with a slurry mix of cement and SBR And laid it back down. Again, the following day, it is loose again.

Do you have any ideas what is going wrong and why this one tile in particular is not sticking? Also any solutions would be appreciated. Thanks

 

[lbstyling]

I have no idea, but.... I am an engineer.

Best guess....

The rest of the tiles are setting, so several things are going on around the tile at the same time.

The tiles around it are setting, and possibly shrinking a bit due to this. That means movement, and at a different rate to your tile.

I have had this in a bathroom, and again on a brick wall. If a wall has a dodgy brick layed when the mix is too dry and you pull it the next day, it just doesn't want to set firm the next day when you re-do it. It could be that the area has drawn the moisture out, and so the second mix needs to be dryer than you expect, or the surface has wet sand on it God knows.

It could also be that the type 1 now has a sandy layer on it from last attempt, and so it can't get a good grip on the stone. If thats the case, you could wet the surface of the type 1 before laying.

Either way, lift the tile, spray with water to wash off any sand on the surface of the type 1. Leave it to go completely dry (weather permitting), and re set. Should win either way.

A real expert may now tell you I'm totally wrong now, and you should use SBR or somthing so am happy to be corrected!