Non-Insulated Door, also called Pan Door
- Has no insulation
- Stamped out piece of a flat sheet metal to form a section
Two-Layer Door
- Insulated
- Stamped door with either Polystyrene or Polyurethane on the inside of the section
Three-Layer Door, also called Sandwich Door
- Steel front with either Polystyrene or Polyurethane Insulation and then finished out on the inside with steel.