Shaped steel sheet:

1. protective film;
2. polymeric coating;
3. passivation treatment layer;
4. primer coat;
5. galvanizing coat;
6. metal.

The 80-mm rock wool core of the sandwich panel has the lowest thermal conductivity ratio as compared with that of other materials such as:

1. standard loam brick (1150 mm);
2. hollow ceramic brick (900 mm);
3. expanded clay lightweight concrete (560 mm);
4. rectangular timber (230 mm);
5. panel rock wool core.