WHAT IT TAKES
Time: 1–2 weekends
Skill level: Advanced
This traditional trim style may look like it requires old-school carpentry skills, but the truth is, it’s easier to install than contemporary trim. Modern trim—four pieces of casing that “picture frame” a door or window—requires wide miter cuts, which look sloppy if they’re not perfect. Traditional trim is more forgiving. While it also requires miter cuts, they’re shorter and less visible. And the most prominent joints are assembled with simple square cuts.
If you’re nervous about installing the mitered crown molding that tops off the trim, check out “Make Your Own Moldings” where we show you how to make a simple router-shaped version that doesn’t require any miters. We’ll walk you through the steps and give you some tips and pointers for cutting and installing the moldings to create this classic trim style.
The first step in any trim job is to prepare the jambs for trim. If you’re replacing trim, pry it off and remove the nails from the jamb. Then scrape or sand the face of the jamb to smooth out any paint or finish that’s built up. Finally, mark the reveal on the jambs to show where the edge of the trim goes (Photo 1, inset). A combination square set to 1/4 in. works great for marking the reveals. But you can also use a compass to scribe the marks, or simply measure and mark the reveals.
If possible, set up your miter saw in the room where you’re installing the trim. Having the saw nearby will save you a ton of time. I like to rough-cut the casing and other moldings to length, allowing a few extra inches, and label them to make sure I have all the material I need and won’t accidentally cut the wrong piece.
For tips on buying or making the moldings you’ll need, see here.
With the moldings and other parts cut to rough length, and the reveals marked on the jambs, the fastest and most accurate method for marking the trim for cutting is to simply hold the molding in place and mark it (Photo 1). It’s foolproof. You don’t have to measure, do math or remember any numbers.
The order of trim installation for windows varies a little depending on whether you’re working on old double-hung windows or newer-style windows. On older double-hung windows, the stool rests on the angled sill and butts into the lower sash (check out Figure A if you’re not sure what a stool is). You have to notch the new stool to fit, and nail it to the windowsill before you install the side casings. But on newer windows like the one shown here, the stool isn’t notched and doesn’t rest on the sill, so it’s a little trickier to nail. An easy way to attach this type of stool is to install the side casings first, and then nail the stool to them (Photo 2).
The stool should protrude past the casings by about an inch (Photo 2). To find the length of the stool, make a mark 1 in. beyond the casing on both sides. Then hold the stool up and transfer the marks. After the stool material is cut to length, round the edges and ends. Or if you want a little fancier stool, rout the edges with a more decorative bit. You can even buy a special stool-shaping bit, but you may have to order it.
With the side casings and stool in place, the next step is to install the apron under the stool. Start by cutting a 45-degree miter on each end. Mark for the long point of the miters by resting the apron on the stool and making marks where the outside edges of the casings intersect the apron material. Snug the mitered apron against the bottom of the stool and nail it to the framing under the window. Then cut returns and glue them in (Photos 3 and 4).
Photo 3 shows how to use a sacrificial piece of wood behind the apron material. Any flat scrap of wood will work. This sacrificial backer board prevents the skinny piece of molding you’re cutting off from getting caught by the blade and flung through the gap in the fence. Don’t attach the sacrificial board to the saw. Just hold it in place along with the molding you’re cutting. Then reposition it with each new cut so you’re always making a fresh cut through the sacrificial board.
The final step for both the door and the window trim is building and installing the head casing assembly. It’s made up of three parts: the fillet, a 1x6 and the cap molding. Traditionally this cap molding was solid, but since a solid molding this large is hard to come by, we substituted 2-1/4-in. crown molding. If you have a router and want to avoid using crown molding, check out Figure B for an attractive alternative.
Start by setting the 1x6 on top of the side casings and marking it at the outside edge of each casing. Cut the 1x6 to length. Then cut the fillet 3/4 in. longer than the 1x6. Round over the edges and ends of the fillet to make a bullnose shape using a router and 1/4-in. round-over bit. Nail the fillet to the bottom of the 1x6.
Finish the head casing by wrapping the front and sides of the 1x6 with crown molding. Photos 5 – 8 show how. Make a jig (Photo 6 and Figure C) to hold the crown molding at the correct angle while you cut it. Remember to set the crown molding upside down in the jig. Mark and cut the short pieces of crown molding (Photos 5 and 6). Then cut a miter on one end of the long front piece and hold it in place on the 1x6 to mark the opposite end for the miter (Photo 7). Cut the second miter on the front piece.
Check the fit by holding the short mitered ends in place against the front crown molding. If the miters are tight and everything fits, complete the head casing by nailing the crown molding to the 1x6 (Photo 8). Complete the window trim by nailing the head casing assembly to the framing above the window (Photo 9).
If you’re installing painted moldings like ours, go to familyhandyman.com and enter “paint trim” in the search box for tips on how to finish your moldings with a flawless coat of paint. You can also find tips for staining and finishing wood by entering “stain trim” in the search box.