Sofa frames can be made of various materials. Manufacturers often combine metal elements, wood, as well as wood stoves in frames: MDF, chipboard, fiberboard, etc. Combinations can be very different. The highest quality is a frame made of natural lumber with a low percentage of humidity (up to 8%). If we are talking about a frame of woody plates, it is worth remembering that they should be well painted and saturated with various compositions that protect the frame from the release of vapors of chemical origin.