... : C style steel, 200*40*2.0mm4) Floor: light magnesium board (our patent)5) Stair: metal6) Roof truss: angle steel7) ... board1 MaterialWall panel sandwich board is made up of foam, polyurethane, and mineral wool, and the top board, back board are steel plate.2 ... board1 MaterialWall panel sandwich board is made up of foam, polyurethane, and mineral wool, and the top board, back board are steel plate.2 ...