Separating planks in intermediate floor?

[Marbu]

Does anyone know what function these lateral separators in the intermediate floor have?

It's not reinforcement as there is cross-bracing elsewhere.

They are aligned with the attic space in the floor, just 20mm thick plank

 

[justusandersson]

Has the wall of the attic space stood directly over this piece of wood? Is it like that all the way or just in this section? When was the house built?

 

[Marbu]

Has the knee wall's wall stood directly above this board? Is it like this all the way or just in this section? When was the house built?

Eksjöhus -84

Likely intended for the knee wall's wall to align, but the upper floor was built privately later and then the wall to the knee wall was moved out.

All sections have this separator

Type of wind barrier? Mouse protection? Or just support for the floor that should have ended there according to the house plan? But unnecessary just for that?

 

[justusandersson]

It is possibly intended as support for a knee wall or as a divider between different types of insulation materials. When it comes to standard houses, you can never be quite sure. The same basic drawing might be used for several different models. A more complete explanation is probably not available. It's a bit like wisdom teeth; if they don't cause trouble, they remain.