ᐅ Is a fast-setting screed necessary for a walk-in shower?

Hello everyone,

My two floor-level showers, which will be tiled, are going to be prepared by the tiler, who wants to use standard concrete screed for the substrate. My contractor had told me that fast-drying screed should be used. So now I’m caught in the middle again. The concrete screed is of course much cheaper. But I also know that concrete screed needs to dry before tiles can be installed. Or can the tiles be laid immediately? Underfloor heating has also been installed in the shower area. What would you recommend? Thanks and have a nice day.

Hello "lars-steina".

First of all, for clarification:
The term "Betonestrich" does not exist! Although you often see this term printed on packaging in hardware stores, it is not an actual term. It is either concrete or screed.
For a barrier-free shower area, a standard cement screed is completely sufficient, but you can also use a fast-setting binder (cement).
Every building material requires time to cure and to release the mixing water into the room air.
Fast screeds (only cement-based for the shower area) develop strength quickly. However, this has nothing to do with the readiness for tiling, meaning the drying behavior!
Certainly, fast cements are more expensive than standard ones, but how large is the area we are talking about? For a few square meters, it is not worth penny-pinching. However, for 500m² (I mean a large area, not just a shower), it becomes interesting to weigh the options.
Ceramic tiles in showers are not installed directly on the screed; first, a waterproofing layer and also the adjoining sealing tapes and corner solutions must be applied. Only then do we install the ceramic tiles on top.
Whether the screed is ready for tiling must be confirmed by moisture measurements. For heated screeds, the screed installer must (or should) mark the spots with plastic flags where the floor layerer can safely take samples without damaging the heating elements.

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Best regards, KlaRa

Drive to the nearest building materials supplier and pick up a few bags of fast-setting screed and leave them there. With regular screed mortar, he cannot properly carry out the waterproofing work nor lay the tiles promptly.
I wouldn’t even want to discuss something like that.
Best regards

Quick decisions based on incomplete knowledge have never provided a serious or reliable basis for making decisions.
Neither standard screed mortar nor any other screed binder can create waterproofing.
Screeds always serve only as load-distributing layers. They are built upon; using Portland cements as well as rapid-setting cements.
Lumping waterproofing measures together with screed binders certainly does not contribute to providing trustworthy answers that a questioner is looking for. However, it certainly adds to confusion!
Those lacking technical expertise should begin with statements like, “... I have once also ...”, but should avoid engaging in the discussion.
Otherwise, unqualified answers will quickly sweep someone off the stage of trust.
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KlaRa

Thank you, KlaRa, for the information. Unfortunately, I have already bought the cement screed. The building materials supplier can’t exchange the bags for fast-setting screed because they don’t stock it. He only offered me PCI Estrifix, which is supposed to turn regular screed into fast-setting screed. Unfortunately, I have no experience with this. Can you help me with this, KlaRa? Or would it be better to just buy fast-setting screed right away?

@KlaRa were you referring to me fully or partially in your reply?

If so, then you are mixing things up here, not me! You cannot apply proper waterproofing to screed that is not fully dried. That is my argument! The idea that screed can or should serve as a waterproofing layer came from you, not me.
I hope what you wrote was not directed at me.
Best regards