slate of different thicknesses

[White Room]

Would'nt use sbr or anythink as an admix for any gypsum plaster, Could alter the setting process.

 

[Spud]

Because of the structure of slate it should not be fixed with sand & cement unless you use a fodifier.

Slate does not absorb as it is made up of layers sheet upon sheet like a laminate these layers dont absorb well, think of roofing slate.

The trick with slate is to get the adhesive to squeeze up between the tiles (not to high obviously) this gives a grab all around where there is more tug available.

Another thing you cant use Lithofin slate seal outside, again because of the structure moisture crawls in from the edges between the surface and the sealer blowing it.

My 2p's worth.


tiler



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i was suprised to see that you dont think slate can be fitted on sand and cement how was it fitted 40 years ago before tile adhesive and modifiers were invented.i respect the fact you are extremly knowlegable tiler and would like you to have a look at this link which gives some good information on slate and installing it with sand and cement Link removed

 

[wetdec]

i was suprised to see that you dont think slate can be fitted on sand and cement how was it fitted 40 years ago before tile adhesive and modifiers were invented.i respect the fact you are extremly knowlegable tiler and would like you to have a look at this link which gives some good information on slate and installing it with sand and cement www.wincilate.co.uk/flooring.htm

he preferred side of the slate tile should be uppermost and the reverse side covered in a neat, Portland slurry of trowelable consistency.

I know what you are saying and I have read the page you pointed me to, the above is a quote from the fixing instructions which as you can see states a neat portland slurry be used. They are using a portland slurry to grab the slate as its a difficult surface effectively a bonding agent. If you lift a tile layed on slurry it will often take a chunk out of the screed.They also use this method when plastering difficult substrates and have done for donkeys years. Sand and cement does not have the viscosity to correctly deal with the surface of slate


tiler


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[Spud]

slurry is essential when fitting all tiles on sand and cement i wasnt specific in my post as how to fix them as i thought it was common knowledge this may help .
1.wet the substrate with clean water dont over flood it
2.pour slurry over the substrate to bond the new bed to the substrate
3 throw your mixture of 4-1 sharp sand and cement on top
4 the bed must be semi dry , so it keeps its shape when grasped in you hand
5. coat the back of the slate with your slurry mixture
6.beat the tile into the bed with a rubber mallet to the required finish floor height
7.the slurry mix is neat cement and water mixed to the consistancy of wall grout
8.when fixing uniform thickness tiles it is possible to screed the floor and tile the same day using neat cement slurry as your bonding coat replacing the need for tile adhesive a retarder is advised to put in your screed mix as the bed dries out quite quickly if you are not careful hope this clears up any confusion with any of my earlier posts

 

[wetdec]

Hey no problem thats exactly what is says on the site you sent me to. You use a slurry which is best practice as sand and cement is not sufficient.



tiler

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