Is lime cement plaster suitable as a base plaster?

Hello everyone,

we had our garage plastered with lime-cement plaster (WebrDdur 110) which was then trowelled.

The plasterer wants to use the same plaster on the base area of the floor slab of our house.

Our construction manager believes that only a fiber-reinforced base plaster should be applied to the XPS boards there.

The base is not part of the property developer’s scope and we can choose freely here.

Who is right of the two?

Can the lime-cement plaster be used or should we take the significantly more expensive base plaster (Sakret KAB)?

Thank you very much

For us, only felting the base and applying silicone resin plaster on the entire exterior facade are done.

Here it is customary for rendered houses:
The base receives sealing slurry already during masonry.
Then the same base coat as the rest of the facade.
Then a synthetic resin plaster from the bucket like Sakret BSP or similar.

We have almost every year the problem that during winter hand-sized pieces flake off near the ground at the base (lime-cement plaster) of the garden fence because lime attracts water and the frost does the rest. We would never use lime products in the base area again, but back then we didn’t know such things. Since a major renovation of the house is planned anyway, only repairs will be done for now until the excavator removes the entire masonry fence and the trouble comes to an end. Get good advice on that.