MDF is a type of hardboard, which is made from wood fibres glued under heat and pressure.

MDF is typically made from sawdust, planer shavings and other waste that remains after a tree is milled into lumber. The wood is then cleaned and mechanically refined in a process that reduces it into fine, uniform fibres. Excess moisture is removed and an adhesive resin is added to hold the fibres together. This mix is then formed into a long, thick, homogeneous mat, which is compressed under intense heat and pressure. The resulting MDF panel is sanded to a fine, even smoothness, and cut to the required width and length. Computer-controlled sensors monitor the entire manufacturing process to measure slight variations that even the human eye cannot detect. Finished panels are tested for uniformity, strength and other structural soundness.

MDF is used extensively indoors in furniture, cabinets, doors, mouldings and flooring. Like other engineered wood products, it has a distinctively flat, dense surface that holds paint well. It doesn't move like wood, so its joints stay tight and paint doesn't crack. But the glory of MDF is its uniformity; it can be machined into every conceivable shape to create architectural details such as balusters or mouldings. Unlike real wood, MDF has no knots, grain or warping that can make intricate woodworking difficult. While solid wood is better suited to structural applications such as floor joists, MDF tends to be cheaper than solid wood so it's well suited to interior doors, bookcases and kitchen cabinets.

In 2002 Premium Quality Distribution Ltd began testing MDF Door Jamb throughout the Pacific NorthWest prehanging door industry email US for more details sales@premiumquality.net