Insulate joists to basement?

[erik211]

I need to replace the floor on the downstairs of my vacation home, and that brings up the question of whether and how to insulate there. Today there are some extra wooden boards as insulation, but they are in poor condition so I need to redo it anyway.

How should one think here? Can regular fiberglass insulation be used? Should it be covered with plastic? Or is cellulose insulation perhaps better?

 

[klaskarlsson]

I need to replace the floor on the ground floor of my holiday home, and that raises the question of whether and how to insulate there. Today, there are some extra wooden boards used as insulation, but they are in bad condition, so I need to redo it anyway.

What should I consider here? Can I use regular fiberglass insulation? Should I use plastic? Or maybe cellulose insulation is better?

If it's a basement/uninsulated concrete slab, you should ensure that no organic material comes into contact with it - to prevent moisture problems.
Maybe EPS or something similar would work with a floating floor on top? Otherwise, a leveling system or something similar.

I would avoid using plastic in the floor of a holiday home, as it seems more likely to trap moisture rather than expel any significant amounts that way.

 

[erik211]

What do you mean by "come into contact with it"? What it's about is the bjälklag between the house and the basement.