Purlins...
 
1. Mineral fiber tiles: 60x60 cm.
2. MDF tiles covered with melamine: 60x60 cm.
3. Corrugated galvanized pre-painted steel sheets.
4. Corrugated galvanized pre-painted steel strips.
 
Walls
The walls are typically made of sandwich panels composed of:• Either a layer of polyurethane injected between two layers of corrugated sheets, or between one layer of MDF and another of corrugated steel sheets, or between two layers of MDF (usually this option is used for internal partitions with an internal layer of polystyrene).
• Interior walls of toilets are made of 2 layers of galvanized pre-painted sheets.