Liquid, elastic, waterproof screed under floor tiles?

In the bathroom and kitchen, floor tiles are to be laid.

To prevent water from seeping down in case of potentially leaking joints or cracks in the floor tiles, a liquid, elastic, waterproof screed should be applied under the tiles.
It can also be an additional layer above the screed.

It is important that this layer above the screed withstands vibrations from passing trucks and working beams in old buildings and does not become porous over time. I have seen something like this somewhere in the past, but I can no longer remember the specific product.

Maybe someone here can give me a product recommendation.

Thank you
Peter

Ready-to-use, single-component, highly elastic, waterproof liquid sealing coating on walls and floors in combination with tiles and slabs. For the sealing of interior rooms according to DIN 18534. Are you thinking of something like this? I don't know if it can withstand truck traffic, but bathrooms with level-access, tiled showers are treated with it. For example, Sopro FlächenDicht flexibel

Here probably more sensible with a sealing membrane, as it is somewhat more crack bridging / elastic. Normally something like Sopro AEB 640, actually sufficient for private use. If you want to be absolutely mega-super-duper-overkill sure, then Sopro AEB HD 958 as sealing membrane - it is also approved for forklift traffic, even if driven directly over it.

Hello questioner.
" had offered you a practical solution for this.
Sure, you can also protect your own trousers from slipping down with suspenders in addition to a belt.
But that is to be considered excessive.
The same applies to the concern that a layer assessed as waterproofing under ceramic tiles, as described in the series of standards DIN 18534, would not meet the requirements in your house.
If the crack situation of your screed is so extraordinary that normal waterproofing systems fail and only a sheet membrane can be used as waterproofing, well, then it was not installed properly (the screed).
However, I assume that it was installed properly.
Therefore, a standard waterproofing system under the tiles is sufficient!
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Regards: KlaRa