shrinkage on some joints—mitered inside corners, ing it butts against.
in particular—are glaringly obvious because you
Cut the first piece of trim square, butt that
can see right into the joint. For this reason, car-
end right into the adjacent wall, and tack-nail it
penters often cope inside corners so that their
up. Coping the second piece of trim is a two-step
meshing profiles disguise shrinkage. Basically, a
operation. First, cut the end with a 45º miter, as
coped joint is a butt joint, with the end of one
if you were making an inside miter joint. Use a
Finish Carpentry
487
pencil to darken the profile of the edge. Clamp
the trim face up. Then, using a coping saw, care-
the Case for not leveling trim
fully cut along the profile created by the miter—
while slightly back-cutting it. If precisely cut,
the older a house, the less likely floors and ceilings will be level. so don’t make
this coped end will mesh perfectly with the pro-
yourself crazy trying to level baseboards and crown molding: you won’t succeed, and
file of the first piece. If you’re not happy with
trim that’s level next to a surface that isn’t will only emphasize the discrepancy.
the fit, shave it with a utility knife or recut it
interior trim, like politics, is an art of compromise. trim edges should be roughly
from scratch.
parallel to floors and ceilings. as master carpenter joseph Beals puts it, “Baseboard
Coping requires ingenuity. If the top of the
is effectively floor trim, and the floor plane is the critical reference, level or not.”
trim curves like quarter-round molding, back-
Mid-wall elements such as chair rails, picture rails, and wainscoting call for yet
cutting would create a little spur that will proba-
more fudging. ideally, chair rails should be level and wainscoting stiles (vertical
bly break off before you can finish the cut, so
pieces) should be plumb, but those ideals may clash with existing trim that’s nei-
don’t back-cut it. Leave the rounded top as a
ther. in that case, split the difference: tack up a length of trim that’s level. then
45º miter, and chisel a corresponding 45º miter
raise or lower one end until your eye accepts the compromise.
into the top of the piece of molding that you’re
trim also can help give the illusion of a level ceiling—helpful, when upper kitchen
coping to.
cabinets must be set level even if the ceiling isn’t. so after leveling and securing
upper cabinets, install a strip of molding to cover the gap above. (you may need to
gluing and attaChing triM
rip it down at an angle.) if you look for it, you’ll see the uneven strip of molding
To increase holding power and keep joints closed,
between the cabinets and the ceiling. But if the cover trim matches the cabinet fin-
apply yellow carpenter’s glue to mating edges
ish, chances are nobody else will notice the difference.
after the casing has been dry-fit and is ready to
install. If you allow the glue to tack (set) slightly,
the casing ends will slide around less as you nail
the trim. But splicing joints with biscuits is by far
the better way to keep them from spreading. Use
a biscuit joiner to cut slots into mating edges,
then inject glue into the slots and spread it evenly
Finish Carpentry Fasteners on the casing ends. Place biscuits in the slots and
reassemble the joints, drawing the joints tight
FAstener
uses
coMMents
with a single 4d or 6d finish nail angled into butt
20-ga. brad
attach small molding returns.
glue returns first.
joints or end-nailed through miter joints. Use a
damp cloth to wipe off excess glue.
18-ga. brad
tack-nail trim while adjusting;
tiny brad holes are easily
attach cabinet toekicks and
filled; easy to pry off
side panels.
tacked trim.
4d (11⁄2-in.)
attach inside edge of casing to rough snip nail point if worried
finish nail
jambs (jambs of rough opening).
about splitting casing.
6d (2-in.)
attach outside edge of 1⁄2-in.-thick
nail should sink at least
finish nail
casing (through 1⁄
1
2-in. drywall) to
⁄2 in. into framing.
rough jambs.
8d (21⁄2-in.)
attach outside edge of 3⁄4-in.-thick
place nails a minimum of
finish nail
casing (through drywall) to rough
3⁄8 in. from edge; snip nail
jambs; attach baseboard; attach
points to minimize splits.
crown molding.
21⁄2-in. to
secure window- or door-frame jambs
Frame jambs twist or flex
3-in. finish-head
to rough openings.
as doors and windows are
screw
operated, so use pairs of
screws at each point.
Double-gluing creates strong joints.
First, use your finger to rub in a little
glue to seal the end grain. When
that’s tacky, apply a second layer of
glue to bond the trim pieces.
488 Chapter 17
Common interior glues
coMMon
cheMicAl
nAMe(s)
pros
cons
brAnds
White carpenter’s,
Moderate strength;
runny; poor initial tack;
elmer’s glue-all®
polyvinyl acetate
inexpensive
clogs sandpaper
Yellow carpenter’s,
strong; good initial tack;
titebond original
polyvinyl acetate
sands well
polyurethane
Bonds to most materials;
glue expansion can spread
gorilla glue; titebond
sands well; takes stain;
joints not tightly clamped;
fills gaps; water-resistant
slow tacking time; stains skin
cyanoacrylate
instant bond; great for
expensive; can’t adjust pieces
super glue; Krazy glue
nonstructural joints;
once placed; skin/eye hazards
bonds many materials
hot glue
Quick-tack glue to create
limited strength, but oK
Bostick®
thin plywood templates
for temporary positioning;
low-stress joints
contact cement
instant bond; resists heat
Can’t adjust once sheet and
dap® Weldwood;
and water; best for attaching
substrate make contact; volatile 3M® Fastbond®
plastic laminate and veneers
solvent; needs good ventilation
* Several websites offer interactive product selectors. Specify how and where you’ll use
the adhesive,
and the selector will choose a product (www.titebond.com is particularly good).
Drive nails into framing whenever possible. If
Casing a Door
framing members are spaced 16 in. on center,
Before casing doors and windows, review
nail trim to every stud or ceiling joist it crosses.
“Checking and Prepping the Opening” on p. 108,
Where trim runs parallel with the framing, as
particularly the remarks on margining, centering
with side casing, nail the trim at the ends and
jambs in relation to a wall’s thickness. Then sur-
roughly every 16 in. in the field. Equally impor-
vey the door and window frames to be cased; use
tant is using the right nail or screw to avoid split-
a 4-ft. level and a square to see if the frame jambs
ting the wood trim. (The table on the facing page are plumb, margined, and square.
recommends sizes for most trim applications.)
To attach narrow molding such as quarter-
Casing eleMents
round, use a single row of finish nails. On wider
molding, use two nails to prevent cupping: Set
Door casing is trim that covers the gaps around a
the nails at least 1⁄2 in. from the edge, and use a
door frame. It goes on after a door has been
square to line up nail pairs.
hung. Most often casing consists of three pieces:
It’s usually not necessary to predrill softwood
two side casings ( leg casings), which cover frame
trim to prevent splits. If you use a pneumatic
jambs, and one piece of head casing, which goes
nailer, do not nail too close to the edge, and don’t over the frame head. Six pieces, if you count both
use too big a nail. However, when nailing hard-
sides of a doorway.
wood trim or nailing the ends of boards, predrill-
There are three common casing joints: mitered,
ing is smart. Use a drill bit whose shank is thin-
preferred for trim that is molded (shaped) because
ner than the nail’s. Alternatively, you can mini-
it enables you to match molding profiles as they
mize splits by using nippers to snip off the nail
converge at a corner; square cut, made with
points, as shown in the top photo on p. 490. It’s a basic butt joints; and corner block, a variation of
bit counterintuitive, but it works.
square cut with discreet blocks at the top corners
Before painting, caulk all gaps between the
and sometimes bottom corners as well. (Bottom
casing and the wall.
Finish Carpentry
489
corner blocks are also called plinths. Top corner
blocks are called caps.)
zzzzzz door and Window Casings
prepping the FraMe
MITERED
Head casing
Jamb edges should extend no more than 1⁄16 in.
beyond finish surfaces. If they protrude more,
1/4-in. reveals
sink any nails, and then plane down the frame.
(setbacks) from
Wall material
If frame edges are level or, say, 1⁄16 in. below the
jamb edges
wall surfaces, leave them alone. If the edges are
sunk more than that, build them up with shim
strips ripped from stock of the same thickness.
Scrape the old frame so that it’s flat, glue on the
strips, tack with brads if you like, and wipe up
the excess glue at once. Also survey the walls
Head jamb
Side jamb
Use an end cutter (or nipper) to snip
Finishing tips
nail points—and wear safety glasses!
Nails with blunt points are less likely
to split trim because they crush the
details on stripping trim, prep work, stains,
SQUARE-CUT OR BUTT
wood rather than wedge it apart, as
clear finishes, and paints are given in chapter
triangular points do.
Thicker head casing
18. here’s a handful of additional tips:
projects slightly
Most trim stock comes smooth enough to
beyond side
paint or stain. if you find rough spots, sand
casing.
them with 120-grit to 180-grit sandpaper
before finishing. if molding has only a few
rough spots, wrap sandpaper around a block for
flat trim or use a sanding sponge for shaped
P R O T I P
1
stock. use a palm sander or an orbital sander
/4-in. reveal
on flat trim with a lot of rough spots.
if you’re installing new or
Side casing
if you apply a first coat of finish or paint
reattaching old door casing or
to the trim before installing it, you won’t need
baseboards, wait until the floors
to worry about getting finish on painted walls
are finished. otherwise, floor
and ceilings. Cut and attach the trim, sand and
sanders and carpet knee kickers
fill joints as needed, sink nail heads, fill holes
can bash the dickens out of trim.
CORNER-BLOCK
with crayon putty, and lightly final sand. apply
the final coat in place, using long brushstrokes
Thicker block extends
Head casing
to achieve a smooth finish.
beyond head and
side casing.
after cutting prefinished trim, wipe saw-
blades with solvent to clean them.
if you decide to finish the trim in place,
tape 12-in.-wide masking paper to the area
around the trim. When the finish is dry, peel off
1/4-in. reveal
the masking paper.
use wax crayon putty to fill holes in pre-
finished trim. avoid wood fillers because their
Side casing
solvent can partially dissolve the finish.
however, if the wood is unfinished, apply filler
before staining it. Filler can be stained and
To repair dings from doors or trim,
sanded, but be sure to test the colors on scrap
hold a hot, damp cloth over the spot,
blocks first.
then apply a steam iron to the cloth
use the smallest possible brads or nails
until the wood swells slightly. Lightly
sand the raised area until it’s level.
to attach the trim, and you’ll have less to fill.
Then use a small artist’s brush to
on dark wood, brad holes are almost invisible.
apply thinned finish to already
finished surfaces.
490 Chapter 17
around the frame, scraping down globs of joint
compound or hammering down (compressing)
high drywall spots that would make the
trim cockeyed.
MarKing a reveal
Boards are rarely perfectly straight, and door and
window jambs (and casing stock) are no excep-
tion. So instead of trying to nail board edges flush,
set the inside edge of casings back 1⁄4 in. from the
frame edges. This setback is called a reveal: It
looks good and will spare you a lot of frustration.
Use the rule of
your combination square as a
depth gauge. Set the rule to 1⁄4 in., and slide along
the edge of the frame, making pencil marks as
you go. Where head reveals intersect with side
reveals, mark the corners carefully.
installing sQuare-Cut
Square-cut casing needn’t be plain. Here, square
door Casing
door casing is spiced up with a 1⁄4-in.-thick beaded
strip between the head and side casing and a beveled
Use a scraper with replaceable carbide
Few frames are perfectly square, so use a framing cap molding.
blades to shave drywall high spots
square to survey the corners. Note whether a cor-
and hardened joint compound. Use a
ner is greater or less than 90º, and vary your cuts
utility knife to cut back shims still
accordingly when you fine-tune the corner joints.
protruding around frames.
Note, too, whether the floor is level because side
casing usually rests on the floor.
First, rough-cut the casing. To determine the
length(s) of side casings, measure down from the
reveal line on the head frame to the finish floor.
Using a combination square as a
marking gauge, make light pencil
(If finish floors aren’t installed yet, measure
marks on the jamb edges to indicate
down to a scrap of flooring.) Cut the side casings
casing reveal (offset) lines. By
about 1⁄2 in. long so you can fine-tune the joints,
offsetting casing and jamb edges,
then tack the casings to the reveal lines on the
you avoid the frustrating and
side frames. (Use 18-ga. or 20-ga. brads.) Next,
usually futile task of trying to keep
measure from the outer edges of the side casings
the edges flush.
to determine the length of the head casing. If
the ends of the head casing will be flush to the
edges of the side casing, add only 1⁄2 in. to the
head-casing measurement for adjustments.
But if the head casing will overhang the side
casing slightly—a 1⁄4-in. overhang is common if
frame, then reposition the head casing so it sits
head casing is thicker than side casing—add
atop the newly cut side casings. Finally, use a
overhangs to your head-casing measurement. Cut utility knife to indicate final cuts on both ends of
the head casing, place it atop the side casings,
the head casing, either flush to the side casing or
and tack it up.
overhanging slightly, as just discussed.
Fine-tune casing joints. Because you cut the
Glue joints. Butt joints are particularly prone to
Renovation 4th Edition Page 114
