Patio adhesive?

[thefurz]

I have spent what seems like weeks laying a patio in my garden with 40cmx40cm limestone slabs. I was about to finish when I noticed some of the slabs have already shifted.

The mortar is solid and has stuck to the old concrete base but the slab itself hasn't stuck to the mortar. Those that have lifted seem to be the last one of each mix I did so I assume the mortar had got too dry.

Anyway, my question is has anyone used an adhesive to stick a slab to mortar? I have a flat mortar base so would rather use a glue than chip them all out again if poss!

Thanks

 

[roberta1000]

Not quite the same thing but I had a similar problem with a wall where a dozen or so bricks on the top course had come loose. I didn't want to chip the mortar off which had stuck well to the second top course in case I loosened some more so I used one of the Evostik ultra exterior 'sticks like s**t' adhesives. Worked fine, still stuck 2 years later but of course it's not so wet at the top of a wall as beneath a slab.

 

[r896neo]

Use a good quality natural stone tile cement.

To be honest it only matter if they have stuck on steps or the outside flag, a solid bed is all thats required if your pointing them.

 

[freddiemercurystwin]

Aye echo r896neo's sentiment, you're more providing a sound base rather than gluing them down.

 

[thefurz]

Thanks all. Will look in to your ideas and maybe post a pic when it is all done!