Quality is more than appearance
- General Installation Instructions
- Installing a Prehung Door Unit
- Pac Trim® Installation Finish and Paint
- Installing Pac Trim® on Metal Stud Wall
General Installation Instructions1
Let Pac Trim® acclimate before installation. Condition Pac Trim® to an indoor environment 48 hours prior to installation. Upon delivery, stack Pac Trim® on stickers or 2 x 4’s above and off the garage floor. If at all possible, crown and coves should be placed on scaffolding or ladders in the same environment they will be installed for acclimation. MDF and wood mouldings will absorb moisture and swell if stored on a concrete floor.2
Proper handling and installation of Pac Trim® mouldings will provide best results that the homeowner will be proud of. This includes protecting Pac Trim® from outdoor environments before, during, and after installation. When installing baseboards, do not install directly onto a concrete floor, and use shims to raise and insulate the MDF from the concrete. This will allow additional time for the concrete to cure and provides adequate airflow to avoid trapping moisture behind your mouldings.
MDF may be hand nailed or fastened with pneumatic finish nailers. When hand nailing, pre-drilling is suggested, but not necessary. If using pneumatic nailers, the recommended air pressure should be 98 to 110 PSI. Installers who have not worked with MDF before should test and adjust the air pressure as needed for their specific equipment. The best fasteners are 15 to 18 gauge brad and pin nails. The type of finish nailer used is up to the installer. It will vary based upon personal preference.3
Carbide tip blades are recommended. They deliver the finest and cleanest cuts and have longer tool life before needing to be sharpened.4
If nailing creates a -blow out- or a -puckering- effect with proper pressure and nail selection, rotate the fastener to a 90 degree angle, or perpendicular with the moulding and apply the nail. Staples and -T- nails may cause a puckering effect and are not recommended.5
The best method to bring miters together starts with a precise, clean cut. Add a bead of carpenters glue and apply one brad nail through the top of the joint down. This will pull and keep the miter together. A common mishap when edge nailing is splitting in a plane parallel to the surface. Using the finer gauge brad or pin will alleviate this problem.6
When installing long lengths of base or crown, do not cut Pac Trim® too tight. Leave a small gap about the size of a credit card at the square end. The coped end will then cover this and a small amount of caulking will complete the corner. When a splice is required, use a 30 degree angle. Glue and pin nail the splice to prevent any separation. In cases of separation it is recommended that a petroleum based painter’s putty be used to repair the separation. Like all wood products, MDF absorbs and desorbs moisture with changes in relative humidity. The normal range of interior humidity is 40 to 80%. The industry standard for maximum expansion and contraction of MDF due to changes in relative humidity from 40 percent to 85 percent is .3 percent. Thus, some expansion and contraction of MDF mouldings should be expected.7
All areas must be free of debris and door openings must be plumb and square.
Suggested tools needed:
- Air compressor
- Air hoses
- Proper pin and brad finish nailers
- Proper pin and brad nails
- Miter saw
- Carbide tip blades
- Hand tools
- Putty (see -Painting-)
- Latex caulking
Installing a Prehung Door Unit
The first method of installing a door unit would be a standard -prehung- flat jamb with no casing attached.1
Attach casing on proper side of door jamb.2
Place door unit into rough opening.3
Raise door off slab 1/4 in. to 1/2 in. to avoid moisture contact with jamb.4
Make sure door is level and plumb.5
Adjust for even reveal between door and jamb (usually about 1/4 in.).6
Use the shims between the door jamb and the framing to assure proper fit. Nail the MDF through the shim into the framing with a 2 in. nail. A 2-1/2 in. nail may be desired, it depends on the installers needs. Do not use a common or a standard finish nail.7
When nailing casing, try to keep from nailing the moulding in the groove or directly on the edge.
Pac Trim® Installation Finish and Paint
All Pac Trim® Products are primed with the unique PacPrime® process. This yields the finest finishing surface possible. Once installed, for best results, fill nail holes with Wood Putty, not caulking. (For putty either an oil base or water base product can be used)
LET WOOD PUTTY DRY. Do not attempt to wipe away putty with a damp cloth. This may enhance the area filled. Sand lightly before applying paint.
Prior to painting make sure the surface is clean. Remove any grease, oil or other foreign materials. Dust, dirt, fingerprints or any minor imperfections may be removed with a scotch brite pad. If you remove the factory prime, you must spot prime before the finish coat is applied.
Then simply paint. The PacPrime® finish will accept any type of paint currently being used in the construction industry; solvent base, water base, acrylic and alkyd paints are all acceptable.
TIPS for installing flat surfaced primed MDF – consider the area the MDF is to be installed. For a half wall top consider using a heavy duty wood glue and apply to the MDF piece that will sit on top of the half wall to eliminate the need for drilling or nail marks on the face of the MDF. Pin or wire nailers present a smaller hole and may be a desired alternative for installing this type of MDF profile. If drilling and nailing is necessary, use wood putty or Mohawk Fil-Stiks, not caulking, to fill holes and let dry completely. Lightly sand when dry. Apply a coat of paint. Lightly sand again if needed. Apply paint and let dry. Note: gloss paint will enhance nail holes and marks in MDF. Take great care when filling, sanding and painting to get the desired finished results.
IMPORTANT: When painting Pac Trim® products, always read your paint manufacturers recommended temperature range for painting and comply with their recommendation.
Installing Pac Trim® on Metal Stud Wall
This is the procedure recommended for installing MDF trim on metal stud walls:12
Use steel stud finish head screws such as Scafco Trim Head 18SQ, #6X2 1/2, instead of nails. There is no need to predrill, as the screw has a self-drilling tip.3
Adhesive such as Liquid Nails can be used in conjunction with screws if desired. Pacific MDF Products Inc./Canadian MDF Products Company does not recommend using adhesive in place of screws.4
Putty over the screw head as you would with a conventional nail and paint the surface.