sive compensates for the screws that don’t grip
holes around outlet boxes.
optimally. Adhesives are frequently used when
Beforehand, shut off the electricity to
applying two layers of drywall, too.
that circuit, and tuck wires well into
When panel edges meet over a stud or ceiling
the box so they can’t get nicked.
joist, apply two parallel 3⁄8-in. beads of adhesive
down the middle of the joist or stud edge. Don’t
make wavy, serpentine beads, which could allow
adhesive to ooze out onto the drywall’s face. On
Fastener Spacing glued joints, space screws every 10 in. to 12 in. on
both panel edges.
maximum
fastener
framing
framing
framing
spacing
HANgiNg DRyWAll pANElS
members
spacing
spacing
with adhesive
Ceilings. Attach ceiling panels first. It’s easier to
ceiling joists
16 in. o.c.
12 in.
16 in.
cut and adjust wall panels than ceiling panels
24 in. o.c.
12 in.
16 in.
should there be small gaps along the wall–ceiling
intersection. Also, wall panels can support the
wall studs
16 in. o.c.
16 in.
24 in.
edges of ceiling panels.
First, ensure there’s sufficient blocking or
24 in. o.c.
12 in.
24 in.
metal drywall clips in place to attach panel edges.
* Fasteners should not be closer than 3⁄8 in. to the panel’s edge.
In most cases, you’ll run panels perpendicular to
the ceiling joists, thereby maximizing structural
434 Chapter 15
strength, minimizing panel sag, and making joist
edges easier to see when fastening panels.
The trickiest thing about hanging ceiling pan-
els is raising them. If your ceilings are less than
9 ft. high, drywall benches will elevate workers
enough. As you raise each panel end, keep one
end low. That is, allow one worker to raise one
end and establish footing before the second
worker steps up onto the bench. Then, while both
workers support the panel with heads and hands,
they can tack the panel in place.
If the ceiling is higher than 9 ft., rent a dry-
wall lift. Because the lift holds the panel snugly
against ceiling joists, it allows you to have both
hands free to drive screws.
Flying solo. If you can’t find a drywall lift or
helpful friends, you can hang ceiling panels solo
by using two tees made from 2x4s. Make the tees
1⁄2 in. taller than the height of the finished ceiling.
Lean one tee against a wall, with its top about
1 in. below the ceiling joists. Raise one end of the
panel up, onto that tee. Being careful not to dis-
with a helper and a set of drywall benches, you can safely raise long panels to the ceiling. Lift one
end at a time. whenever possible, run the panels perpendicular to the joists.
lodge the first end, slide the second tee under the
other end and raise it until the entire panel is
snug against the ceiling joists. (Staple strips of
rubberized carpet pad to the tee’s top to reduce
slippage.) Gradually shift the tees until panel
edges line up with joist centers. Be patient and
wear a hard hat.
Walls. It’s easier to hang drywall on walls than
on ceilings. Although one person can usually
manage wall panels, the job always is easier and
faster with two. Before you begin, be sure there’s
blocking or drywall clips in the corners to screw
panels to. To help you locate studs once they’re
covered with drywall, mark stud centers on the
top plates (or ceiling panels) and sole plates at
the bottom.
If the ceiling is higher than 9 ft., and especially if it’s a cathedral ceiling, rent a drywall lift.
P R O T I P
Mark joist centers onto the top
of the wall plates before you
Install the top wall panel first,
install the first ceiling panel.
butting it snugly against the ceiling
panel. At the same time, level the
That will enable you to sink
bottom edge of the wall panel so that
screws into the joist centers
subsequent panels butted to it will
when they’re covered by drywall.
also be level and correctly aligned to
The pencil marks will also help
the stud centers.
you align screws across the
panel, simply by eyeballing from
those first screws to the uncov-
ered joists on the other side.
Finish Surfaces
435
Corner bead protects fragile drywall edges and
To prevent cracking along an outside corner, this installer
ensures a clean finished edge.
covers the edges of the corner bead with mesh tape before
applying a setting-type compound.
When hanging wall panels, professionals
are, the more taping and sanding. Anyway, dry-
often start with the top panel, butting it snugly to wall panel isn’t expensive. So, when in doubt
the drywall on the ceiling. By doing so, they min-
about reusing a piece, throw it out.
imize gaps and support ceiling edges better.
Curves. Curved walls are easy to cover with dry-
Important: If you’re installing wall panels hori-
wall. For the best results, use two layers of 1⁄4-in.
zontally, the top panel edge must be level and the drywall, hung horizontally. Apply construction
butt ends plumb. Otherwise, subsequent panels
adhesive between the layers. Stagger their butt-
may be cockeyed and butt ends may not be cen-
and bevel-edged joints. For an 8-ft. panel run
tered over the studs.
horizontally, an arc depth of 2 ft. to 3 ft. should
Once the upper wall panel is secure, raise the
be easy to achieve. Sharper curves may require
lower panel(s) snug against it. A homemade panel back-cutting panels (scoring slots into the back
lifter is handy because it frees your hands to align so that the panels bend more easily), wetting
the panels and sink the screws. A panel lifter is
(wet-sponging the front and back of the sheet to
simply a lever of scrap wood set with a fulcrum
soften the gypsum), or special-ordering flexible
in the middle. Pressing down on one end of the
drywall panels, which have facings better suited
lever with your foot raises the other end, which
for bending.
lifts the panel, as shown in the bottom left photo
Corners. Corner bead reinforces and protects
on p. 424.
outside corners, uncased openings, and the like.
Doors and windows. Joints around doors and
It’s available in many materials. For best results,
windows will be
weak and are likely to crack if
install it in a continuous piece from floor to ceil-
panel edges butt against the edges of the opening. ing. Cut the bead for outside corners about 1⁄2 in.
That is, run the panel edges at least 8 in. past
short: Push it snugly to the corner and slide it up
door or window trimmers, and cut out the part of until it touches the ceiling. The 1⁄2-in. gap at the
the panel that overlaps the opening. Pros do this
bottom will be hidden by baseboard.
because framing twists and flexes slightly when
Galvanized metal bead was at one time the only
doors or windows are opened and closed, which
type available, and it’s still widely used. To cut it,
will stress drywall joints and cause them to crack. use aviation snips (also known as tin snips). The
Expect to waste a lot of drywall when cutting
metal bead goes on the outside corners before
paneling for doors and windows. Old houses are
the tape and joint compound are applied. Nail it
rife with nonstandard dimensions and odd
up, spacing nails 8 in. apart, on both legs of the
angles, so don’t fight it. You can use some of the
bead. Then cover it with compound.
larger cutoffs in out-of-the-way places such as
closets, but remember that the more joints there
436 Chapter 15
Vinyl bead is less rigid than metal and able to
accommodate outside corners that aren’t exactly
90º. Attach vinyl bead either by stapling it directly
to the drywall, spraying the drywall corner with
vinyl adhesive before pressing the bead into the
adhesive and then stapling, or using a taping knife
BeDDIng The TApe
to press the bead into a bed of joint compound.
Paper-faced beads are embedded in joint com-
pound. One of the best is the Ultraflex® structural
corner, which comes in varying widths and has a
plastic spine that flexes in or out so it can rein-
force inside or outside corners. Because they’re
flexible, such tapes are great for corners of just
about any angle.
TApiNg AND FiNiSHiNg
To finish drywall, seal the panel joints with
tape—or cover corners with corner bead—then
spread joint compound over them. Typically,
three coats of compound are applied in succes-
sively wider coats and sanded after each applica-
tion. The first coat, usually a high-strength taping
compound, beds the tape. The second coat
should be a thin layer of topping compound or
all-purpose compound that you feather out to
hide the joints. With the third coat, you feather
out the compound farther, creating a smooth, fin-
ished surface. (See “Joint Compounds” on p. 428
for more about these materials.)
1. Before applying paper tape, cover the seam with a
2. After using your taping knife to
generous bed of joint compound.
center the tape on the seam, press the
tape into the joint compound.
4. Use a 10-in. knife to apply the second coat of
5. Applied correctly, the third coat
compound.
should need only hand-sanding. A
dry-sanding block is great for light
3. After applying a layer of compound over the tape,
sanding and corners.
remove the excess. If the tape moves, you’re pressing too
hard or your taping knife needs to be cleaned.
Finish Surfaces
437
First coat. Fill nail holes or screw dimples by
P R O T I P
applying compound in an X pattern: One diago-
An ORDeRLy Finish
nal knife stroke applies the compound, and the
Apply joint compound gener-
second diagonal stroke removes the excess.
ously. Without enough mud, the
all that raw drywall can seem a bit overwhelm-
If you use paper tape on the joints, first apply
tape won’t stick. But as you
ing, so here’s a taping and mudding sequence
a swath of taping compound about 4 in. wide
feather out the wet mud, scrape
that starts easy so you can become comfortable
off excess; sanding off dried
down the center of the joint. Press the tape into
with the tools and materials:
globs later would be tedious and
the center of the joint with a 6-in. taping knife.
screw and nail holes
time-consuming.
Then apply compound over the tape, bearing
bevel-edge joints (the long edges of panels)
down so you remove the excess.
butt-edge joints
If you use self-sticking mesh tape, stick it
outside corners
directly over the joint and apply the bedding
compound over it. In other words, don’t apply a
inside corners
bed of compound first when using mesh tape.
have a pail of clean water and a sponge handy
Mesh tape must be bedded in setting-type com-
so you can rinse your taping knives periodically.
pound, as explained earlier in this chapter.
they glide better if they’re clean. keep the job
Allow the first coat to dry thoroughly before
site clean, too: if you drop a glob of compound
sanding it. This will take about a day, if the room
on the floor, scrape it up and discard it so you
temperature is 65ºF to 70ºF and there’s adequate
don’t track it around the house.
ventilation. Sand lightly with 120-grit to 150-grit
sandpaper. Because there are two more coats to
come, this taping coat can be left a little rough.
Second coat. The second coat is also called the
angle and pressure, the more compound you’ll
filler coat, and with this one you’ll apply the most remove. This is easier to do than explain.
compound. At this stage, many professionals use
Because butt-end joints are not beveled, they’ll
a 10-in.-wide taping joint knife and feather out
mound slightly at the center of the seam. That’s
the seams so they are roughly 8 in. to 10 in. wide. OK. Use a 10-in. taping knife to build up the
After applying the compound, smooth it out with compound on both sides of the joint, feather out
an even wider blade—say, a 14-in. trowel.
the edges, and smooth the center. Consequently,
As you’ll learn when working with joint com-
butt-end joints may need to be wider than bevel-
pound, the lower the angle of the blade and
edge joints. You may often need to feather butt-
the less pressure, the easier it is to smooth and
end joints 16 in. to 20 in. wide.
feather (spread out) the mud. The greater the
When this second coat is dry, sand with
150-grit to 220-grit paper. A pole sander will
extend your reach and enable you to sand longer
without tiring, but don’t sand too aggressively or
The Art of inside Corners
you’ll abrade the paper face or expose the tape.
Use paper tape for inside corners.
Easy does it.
After applying a bed of compound t
o
Third coat. The third coat is the last chance to
both surfaces, crease the tape and
feather out the edges, so use a premixed, all-
place it in the corner. Then use a
purpose, drying-type compound, which is easy
double-edged corner knife (see
to thin out and sand because it has a fine consis-
p. 425) to press the tape into the
tency and dries quickly. Although premixed com-
compound before spreading a layer
pound will be the right consistency, it’s OK to add
of compound over the tape.
a little water to thin it even more.
Because the third coat is only slightly wider
Some pros snort at corner knives,
(2 in.) than the second coat, you’ll be applying a
preferring to use a flat 6-in. taping
relatively small amount of compound. Use a
knife to press tape into compound,
12-in. trowel, with a light touch. Some pros thin
one edge at a time. When feathering
this coat enough to apply it with a roller and then
out joint compound, pros allow the
smooth it with a trowel. They leave no trowel
compound to dry on one side of the
marks when they’re done.
corner before working on the adja-
Hand-sand the final coat, using fine, 220-grit
cent surface. in other words, “Never
sandpaper or a very fine sanding block. Shining a
run wet mud into wet mud.”
strong light at a low, raking angle on surfaces will
highlight the imperfections you need to sand.
438 Chapter 15
Wrap up. If you intend to texture the surfaces,
the third coat doesn’t need to be mirror smooth.
Mechanical TAPinG TOOLS
Even so, don’t scrimp on the second coat, or else
the joints may be visible through the texture.
mechanical drywall taping tools are
To give yourself the greatest number of deco-
commonly referred to as bazooka®
rating options in the future, paint the finished
tools, after a popular brand, and
drywall surface with a coat of flat, oil-based
they can be rented, usually for two
primer. It will seal the paper face of the drywall
weeks at a stretch. the suite of
and provide an excellent base for any kind of
tools includes a taper that applies
paint or wall covering.
tape and compound simultaneously,
DRyWAll REpAiRS
as well as finishing tools, various
head attachments, and flat boxes
Renovation 4th Edition Page 102