Installing decorative trim around an entry door—whether old or newly installed—is a quick way to give your house a facelift. With the advent of urethane foam molding, there is now a wide range of affordable molding styles to choose from.
Urethane foam trim is light, paintable, easy to cut, and will never rot—ideal for exterior trim. The trim shown here can be purchased at a home center. For a larger selection, check online sources. You may need to measure your door and order the header—the horizontal piece at the top—at a certain length. The casing (the vertical pieces that replace the brick molding) can be cut to length.
It will take most of a day to install decorative trim around an entry door. Before you begin, you'll need to measure the doorway and buy the trim pieces. It's also a good idea to protect the area with a drop cloth.
What You Need
- Drop cloth
- Tape measure
- Flat pry bar
- Circular saw
- Utility knife
- Nail set
- Caulk gun
- Putty knife
- Sanding block
- Urethane foam moldings to fit your doorway
- 6d and 10d casing nails
- Adhesive recommended for your moldings
- Exterior caulk
- Exterior putty
Step 1: Remove Existing Molding
Using a flat pry bar, carefully remove the brick molding from around the door. Be careful not to dent the siding or the jambs; using a scrap of wood as a fulcrum helps.
Step 2: Scrape Off Any Extra Paint
Scrape away any accumulated paint or putty from the jamb. If the reveal line is not clearly visible along the jamb edge, scribe a reveal line. If needed, seal and insulate the gap between the jamb and the framing with non-expanding spray foam insulation.
Step 3: Measure for Header
To establish the width of the header (the piece above the door), hold each piece of casing in place and mark along its outside edge. Measure between the marks. The header looks best if it extends beyond the casing; add twice the thickness of the header to the overall length and mark for cutting.
Step 4: Miter Ends of the Header
Miter the ends of the header. Urethane foam cuts as easily as wood, but if the saw blade binds and overheats, a hard crust will build up. If this happens, pare off the crust with a utility knife.
Step 5: Glue and Tape
To assure that the header will stand proud of the casing, glue in place urethane parting stop along the inside of the top and bottom of the header. Cut small mitered pieces of the header to create a return. Glue and tape both pieces in place.
Step 6: Cut and Attach Casing
Cut the casing to length. Position each piece of casing and check that it meets against the reveal line. Drill pilot holes and attach the casing with 6d casing nails driven into the jambs and 10d nails driven into the sheathing and studs.
Step 7: Set Header in Place
Set the header in place and center it so it extends equally beyond each piece of casing. Drill pilot holes and fasten it as you did the casing.
Step 8: Set Nails and Caulk
Set the nails and fill with exterior wood filler. Sand the filler when it is dry. Apply exterior-grade caulking all around where the molding meets the siding.