Slate stuck or not, help.........???

[mmmadman]

Hi all, this is my 1st post on this great site.

I started laying an 18m sq slate patio on my existing 600 x 600 concrete slabbed patio which has been down for years. I am using 300 x 300 x 10 natural slate from Wickes and I am creating a pattern with diamonds and small squares. Joint size is approx 10mm.

The Problem
Day 1, I laid three rows using a bed of approx 10mm sand and cement 5-1 wet mix (recommended by a builder mate)

Day 2 I started the pattern and laid about a third of the total area, using the same mix.

On day 3 I went outside and it was raining a bit and I noticed that some of the tiles that I had laid on day 1 moved when I stepped on them and I was able to lift them by hand too. The tiles that I laid on day 2 seemd ok but I did not lift any.

Now one week later all of the area I did last week seems firmly bonded except the ones that I actually lifted that were laid on day 1.

Were the tiles still curing and is it ok to leave them now or do I have to take it all up and use a prority adhesive? what happend?

I intend to seal and then grout with the correct grout not mortar.

I hope I hav explained the problem ok, many thanks............

 

[mikethetile]

I take it that its only the ones that you lifted that are not stuck, if so take up the bed and relay them

 

[TT Tiling]

hi mate i would of layed them all with flex add and grout , did about 100sm around my place 5 -6 years ago .not one has ever come up and the grout joints are still like new ,just jet wash once a year looks like new

 

[mmmadman]

Yes only the ones I lifted are not stuck now.

Is it ok for me to carry one as I started....???

Cheers.................

 

[mikethetile]

yes it is

ive laid slate on sand cement without problems

 

[Houston]

3 in 1 wet mix with pepper pot sprinkle method

 

[White Room]

10mm sand/cement could be to thin for outside fixing, what sand did you use

 

[david campbell]

Would have used a 3;1 ratio for the mix

 

[Spud]

did you slurry the backs of the tiles ? if you didnt then they will come up clean as whistles ,mix a neat cement slurry, when fixing and paint the slurry on the back of the slate before bedding the tiles in ,then you wont have any further problems

 

[nybor62]

im with gary on that

 

[mmmadman]

did you slurry the backs of the tiles ? if you didnt then they will come up clean as whistles ,mix a neat cement slurry, when fixing and paint the slurry on the back of the slate before bedding the tiles in ,then you wont have any further problems

I'm a bit lost here, what is a slurry, is it just water and cement and if so how thick a consistancey should it be/

Also nobody has mentioned whether I should start again or leave the slate that seems to of stuck?

I just used Wickes building sand (rich Red colour) and blue circle cement.

Many thanks...................

 

[mmmadman]

Many thanks for the replies so far..............

Having had a closer look at the weekend I have decided to start again.
The slates came up really easily so non of them were stuck properly, non broke out of a 6m sq area the mortar had just really stuck to the concrete slabs.

I managed to get the motor up with a spade and some hard graft and swearing.

I have bought some BAL adhesive and layed a few last night, it seems a great product and easy to work with and the slate tiles really grabbed so hopefully it will be ok this time......!!!!

Cheers.................

 

[mikethetile]

you should be ok now

sand /cement was the old way and required a mallet to set them as it rose the fat from the mix to adhere the tile. also as mentioned a slurry coat could be used