What board materials do you use: particleboard, MDF, plywood or solid wood?

We work with particleboard (chipboard), MDF, plywood, OSB and solid wood, each for a different job. Carcasses are most often moisture-resistant particleboard or plywood; painted and profiled doors use MDF; plywood is specified where screw-holding, moisture or weight matters; solid wood is used for frames, feature panels and premium doors. The right choice depends on the room, not on a general ranking.