Hello!
I have removed the cast iron floor drain and discovered that my slab consists of the following:
15 cm concrete
5 cm stone wool board
Plastic
Sand
My question concerns the plastic, which I assume is there as a moisture barrier. I assume that in the seventies they thought it was good to have it there to prevent moisture from below from making its way up into the slab. And it probably does that, the sand below felt significantly more humid than the insulation above, but won't it also contribute to condensation forming on the inside of the plastic?
I have no plans to remove the plastic or change anything in the construction but am more interested in what the purpose of the plastic is and whether it contributes to anything or is completely unnecessary?
I have removed the cast iron floor drain and discovered that my slab consists of the following:
15 cm concrete
5 cm stone wool board
Plastic
Sand
My question concerns the plastic, which I assume is there as a moisture barrier. I assume that in the seventies they thought it was good to have it there to prevent moisture from below from making its way up into the slab. And it probably does that, the sand below felt significantly more humid than the insulation above, but won't it also contribute to condensation forming on the inside of the plastic?
I have no plans to remove the plastic or change anything in the construction but am more interested in what the purpose of the plastic is and whether it contributes to anything or is completely unnecessary?
I believe it is there to function as a capillary-breaking layer. In the 70s, under-insulated slabs were built. Either with leca balls, which were then thought to be capillary-breaking but turned out not to be. They were, of course, aware of breaking the capillary action. What else is good for that? Plastic, of course. So it is a fully logical construction for building a slab on the ground with an under-insulated slab where the floor covering lies directly on the concrete slab.