hi paul
i have seen a few failures in the last 18months with tile fixing straight onto screeds,without proper prep..
they have all been gypsum "anhydrite" screed, tiles just "blowing" off,
just about every house builder out there now are using this type.
its only 40mm thick to the 75mm sand/cement one, so curing time is a lot quicker.
so i always ask what type of screed it is,then sand it down to remove laitance then a good few coats of recommended primer.
tictic’s right Paul; Gypsum & Anhydrite screed contains calcium sulphate as does Gypsum wall finish plasters & most base plasters. Cement power adhesives will react with an unsealed Gypsum base & can blow the tiles so be sure & check in future.
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local