I'm trying to figure out if it'd be possible to lay old roof slate as a flooring. I've found some really big old slates at a salvage yard and think they could look really good as a floor in my hall. The house is an old partially converted barn and the hall is quite big.
The problem will be how to lay them as they're very thin - maybe 5 to 10 mm or so. I reckon they would look like huge old flags and once laid and you wouldn't know that they were so thin. Any suggestions on how to lay them so they will be solid and not break / crack easily

Hey don't think that'll be a problem if you go about it in the right way to give the slates a completely solid base so there are no gaps or air trapped as you lay them.

Am assuming you've got a solid floor there at the moment. Lay them on a very wet screed would be my advice. Have the mix higher than needed then as you put each one down sit it into the screed at one end and then drop it slowly to ensure no voids. If you then work it down into the mix you should be able to get it in full contact as you level it with previous ones.

Probably best to work a small area at a time to avoid disturbing previous slates too much

Thanks What sort of mix would you suggest for sand and cement