Polyurethane crown mouldings and trim can be installed very much the same as wood crown mouldings and trim.
For a better crown moulding fit, it is suggested that a flat “Butt Joint” is utilized to join the polyurethane crown mouldings together in the middle. Cutting the individual parts 1/8th of an inch longer than than you measure, fitting the left and right sides in place first and then middle pieces last is recommended for a tighter fit.
Place a long bead of construction adhesive on any surfaces touching the wall or ceiling prior to installing the crown moulding. A good polyurethane glue or crazy glue is handy for attaching lengths together to insure a long term fit. An are nailer works great for fastening polyurethane crown mouldings window casings and door casings to walls and ceilings ; or, screws may be used being careful to finishing any holes left behind with a paintable filler.
Filling and Sanding
Once all of the crown mouldings are put up, fill any joints between the mouldings or with a paintable latex caulking or spackle. The same product may be used along the top and bottom edges of the crown moulding where it meets the cornice, ceiling or wall. A damp cloth can be used to clean any excess material to leave a good professional appearance.
All nail or screw holes may be covered with the same paintable non-shrinking filler. Be careful not to sand yoru crown moulding or decorative trim too much. Sanding past the outer skin may require further filling and sanding to create a fully paintable surface.
Ceiling Medallions
Place a solid bead of premium adhesive around and about the backside of the medallion. Pressing the medallion into place, it may then be secured with 4 trim head dry wall screws. Be sure to place the screws so that any holes created may be filled and sanded with minimal effort.
Wall Niches
Some surface mount wall niches may be hung temporarily using attached hardware or permanently using the same applicator procedures as for Ceiling Medallions. Other niches available come complete with their own template and installation instructions.
Pro-Flex™ Flexible Mouldings (No longer available, 2008)
Let the material acclimatize to room temperature. Mouldings handle best between 18c and 22C (65°F & 72°F). Do not soak the crown mouldings in hot water. For INSIDE curves, measure the length required and add 1/8 inch. Dry fit the moulding, shimming and trimming as necessary to get the perfect fit.
For OUTSIDE curves, measure but don't trim the moulding for extra material. Clamp tape or wedge the material in place. For INSIDE curves, start in the middle of the piece and work evenly on either side to the ends so the material is not stretched and flat spots in the curve are eliminated.
Check the thickness of the product to the thickness of the matching wood moulding product where the two will meet. It may be necessary to shim or plane off either product to have material align properly.
Predrilling all nail or screw holes are recommended for best application. Alternatively, an 18 gauge pneumatic pin nailer may be used to fasten the moulding in place. We recommend that all nails or screws are placed no closer than 3/8 inch from the edge of the crown moulding, window casing or door casings.
Do not use staple guns
Do not overstress the material
Fill and lightly sand the material as for wood, taking care not to damage any surface, wood grain pattern.
The crown moulding should be clean before painting or staining using a non corrosive cleaner.
