Medium-density fiberboard is a sturdy building material made with a treated combination of wood fibers and adhesive to form a lumber-like medium used in a variety of applications. This type of fiberboard is often manufactured using particulate from both hard and soft woods, which makes it a very dense material.
Medium-density fiberboard, commonly abbreviated as MDF, is a versatile construction medium and can be used in almost every project as a substitute for real lumber. Unlike real lumber, fiberboard is less likely to warp. Manufactured fiberboard products are commonly cut in the same sizes as real lumber and can be found in most home improvement stores.
There are many types of MDF, including products that are moisture resistant and fire retardant. The material is substantially heavier than regular lumber due to its composition.
MDF is especially prone to crushing or marring if not handled properly. It is generally made with a hard surface but a soft inner core, which sometimes breaks or chips when installing a nail or screw.
Moisture can cause the material to blister or curl.
MDF produces a significant amount of dust when it is cut or sanded, which is why FamilyHandyman.com recommends donning an air-filtering mask and safety goggles when working with the material.