MDF Crown Molding

MDF (Medium Density Fiberboard) Crown Molding (or Moulding) is a type of hardboard which is made from wood fibers glued under heat and pressure.  Crown molding is a wonderful style flourish that can blend the wall and ceiling together and add some architectural beauty easily.

MDF crown molding can be used for various reasons. It’s a good alternative material to use and comes in different sizes and designs.  It’s less expensive, but has the same elegant look.  It has density, it is stiff and flat and it doesn’t have knots.  It is easily machined.  It doesn’t have an easily recognizable surface grain because it is made up of very fine particles.

MDF crown molding is easy to paint and produces a smooth quality surface.  Because there is no grain, it can be cut, drilled, machined or filed and there will be no damage to the surface.  MDF crown molding can be glued together with PVA wood glue.  Any oil or water-based paint or varnish could be used on MDF.  You can also use a veneer or laminate to finish MDF.

Installation of MDF Crown Molding

You should choose the size based on the height of your walls.  MDF crown molding generally comes in 4, 5, 7 and 9 inch wide pieces, and usually 8 feet in length.  As in ordering other stock, allow for about 10% waste.

You can finish the crown molding before installation.  After marking the studs, cut the length of both walls in a room on each side of a corner.  You can pre-drill the molding at the stud marks and then nail it.  As with other molding, you can use scarf joints to join pieces on long expanses of wall.

You can use MDF crown molding corner blocks which eliminates the need to miter or cope.  The ends of the crown molding coming from each direction insert into slots on either side of the corner blocks, which are then nailed into the corner.

Some people find that gaps appear after a time following installation.  It’s important to make sure the crown molding is nailed securely, since MDF can droop or sag if the nails aren’t secure.  A large, 16 penny nail can be driven through the center of the crown into the plate to draw it tight against the ceiling and wall at the same time.  Always nail into the studs.  A good quality adhesive caulk can be used around the edges once the piece is securely in place.

MDF crown molding can be an ideal alternative to wood for practical and professional-looking crown molding installation.