Outside steps....problematic!!!!

[Perfect Tiling]

Hi guys.....been asked to do a very large set of outdoor steps that form the main entrance to a very nice house...however...there is a problem. The tiles are coming loose after another tiler refixed them two years ago after they came loose then. Behind the tiles seems to be a layer of possibly limescale coming from the substrate and pushing the tiles off. The substrate is poured concrete with a smooth render which has been down for about 10 years or so. Is there any way of stopping this limescale from coming through the steps. I dont want to go and tile the job for the same thing to happen in a couple of years time. Cheers in advance.

[diamondtiling]

If you remove the tiles and use a powerwash to get rid of the limescale you could use an epoxy sealer before fixing the tiles again.
What adhesive are you planning on using?

[Dave]

Is it not efflorescence..? and were they solidly fixed to prevent frost damage/blowing.

[jay]

Think this is more a question of what products were used
was the adh suitable for outdoor conditions and was a pva used
think the smooth render may need roughing up to allow the adh to get a bite

[Gall.B]

Where the original tiles re-used? and is what your pricing to do also?

[Perfect Tiling]

Thanks guys...sorry but had to dash out last night. Diamond...plan to use BAL SPF as it will go down to -30 degrees (house on norht coast of Scotland!!) Dave...they seem to have been on a solid bed. Don't thing itsefflorescence as is only behind the tiles and not even through the grout. The "limescale" appears to keep growing and pushing the tiles off...if that makes sense. Jay...sorry I don't know what was used to fix them the last time as I had nowt to do with it...I really want nowt to do with it this time but the guy also has properties he rents out so may get other work. He plans to clean and reuse the original tiles. I thought about a sealer once the steps were cleaned but wondered if the stuff is coming out of the tiles...will it not just push out the sealer in the same way?

[jay]

need to know what the tile is if you dont mind

[Gall.B]

maybe steep the tiles overnight and dripdry to get suction back into them.

[Perfect Tiling]

Tiles are porcelain...but I don't think it is the tiles that are the problem. The adhesive is stuck solid to the back of the tiles. I remember a relations house had a similar problem with their brick facing that was stuch to concrete...the bricks started to go white and eventually crumbled away....I think that was salt coming through from the back. Oh....give me floors and walls every day...

[jay]

might be easier if you post some pics as i think the problem is adh or is the landing holding water (puddling)