Does a vapour barrier need to be installed with standard insulation screed?

For the installation of standard insulation screed in the Staenis grid, you may use a foil. Afterwards, it can be covered with OSB or Durelis tongue and groove boards.

For the installation of standard insulation screed as a levelling layer (without Staenis grid), always install without foil.

You can improve the adhesion of the standard insulation screed by moistening the concrete substrate with water the evening before.