Traditional vs. modern trim
This traditional trim style for windows and doors 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 window and door trim, check out
“Make Your Own Moldings” below, 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.
Time: 90 minutes per
window or door.
Cost: $35 per
window and $40 per
door for pine trim. Oak
or maple trim would
cost about twice as
Tools: A miter saw
with at least a
40-tooth blade. A
pneumatic trim nailer
and compressor, and a
table saw and router
with a 1/4-in. roundover
bit if you want to
make a stool and fillet
like the ones shown
Prepare the jambs
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. 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 “Traditional molding” below.
Mark the trim, don't measure
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
Window and door trim parts
Figure A: Window Trim Parts
Trim terminology can be confusing. Here's a labeled
photo to show you the names of the window trim and door trim parts we used.
Install the window casings, stool and apron
The order of trim installation for windows (and door trim as well) 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 I used 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.
Hold the wood with featherboards.
Build a simple push block to rout ends.
Figure B: Router-shaped cap molding
Tips for Choosing, Buying and Making Your Own Traditional Molding
Shopping for trim
We found the wide casing and base blocks
at the home center, along with the fancy
casing we used as an apron. We had to go to
the local lumberyard for the 2-1/4-in. crown
molding. If your local home center or lumberyard
doesn’t have what you want in
stock, ask to see a molding book or chart
that shows what styles are available to
order. The Internet is also a good place to
search for traditional moldings for door trim and window trim. Here are a
few links to help you get started.
Make your own moldings
You don’t have to buy moldings. With a little
ingenuity and a few standard router bits,
you can make your own door and window trim. Figure B shows an
example of a cap molding for a head casing
that we made by stacking two pieces of 3/4-
in. oak. Shaping the edges of wood strips
with a router and stacking them to make
bigger moldings is a great technique for
making your own moldings.
You can make moldings with a handheld
router, but it’s a lot easier and faster to
mount your router in a router table. The
Ryobi router table shown here (about $100)
works well, but there are plenty of other
options. For plans to make your own, see this DIY router table .
The photo shows how to use
featherboards for safer and more accurate
routing. You can make your own featherboards,
or buy plastic ones like the ones in the photo for
about $10 to $20 each.
The ends of the boards shown in Figure B
are routed. This method eliminates the need
for mitered returns, but it does expose end
grain and means you have to cut the parts
to length before you shape them. To rout the
end of boards, use a shop-made push block
like the one shown here. It
serves two functions. First, it allows you to
hold the board square to the fence. And
second, the push block prevents splintering
by providing a backer behind the board
Build the head casing assembly
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 above 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).
Cutting jig for crown molding
Figure C: Crown Molding Cutting Jig
This jig holds the crown molding at the correct angle in
the miter saw, so it's easy to make accurate miters every
time. Glue two strips of scrap wood together at a right
angle. Then set the crown molding upside down in the jig
and mark the position of the stop. Glue the stop to the
bottom and you're ready to cut some moldings.
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A DIYer's success story
Matt Timpany finished a
huge empty room in his
basement into a home
theater, pool room,
game room and full
Matt’s an avid, self-taught DIYer with 15 years
of woodworking experience. For this 1,400-sq.-ft. basement remodel, he went a little
outside his comfort zone and also tackled
the wiring and plumbing, which he did successfully
except for one plumbing mistake,
which, in Matt’s words, led to some “training
cost.” Between his dad job and his day job,
this project took Matt two years and three months to finish.
Door trim is similar
Trimming a door is just like trimming a window, except
you start out with base blocks at the floor, as shown here.
The base blocks should be about 3/8 in. wider than the
casings. Trim them if necessary. The height of the base
blocks should be about 1 in. greater than the height of the
baseboard you're planning to install.