 |
Installing Colonial Baseboard
With Coped Corner Joints
|
In
This Article:
Wide baseboard is installed over a
hardwood floor, using scarf joints and cope-cut ends.
Problems with the uneven floor and imperfect corners are
addressed. |
Related Articles:
|
| Skill Level:
3 (Intermediate) |
Time Taken:
A Day Or Two |
By
Bruce W. Maki,
Editor
Start:
While remodeling a room in the
second floor of my 1960's one-and-a-half story house, I
decided to replace the original plain and narrow baseboard
with a wider traditional base board.
| After
finishing the hardwood floor and painting the
walls, I was ready to
install the baseboard. |
 |
|
Before Installing Baseboard...
These steps should be complete
before base board is nailed to the walls:
-
Walls already painted
(preferred, not required).
-
Door casings installed
(baseboard butts up against door casing). If using
traditional trim, at least the plinth blocks need to
be installed.
-
Studs located with stud
finder.
Pre-Painting The Trim: The
trim I bought came pre-primed. I gave the trim a light
scuff-sanding with 120 grit sandpaper, then I brushed
off the dust and applied one coat of semi-gloss interior
paint. When the paint was dry, I scraped off any excess
paint that had drooled onto the back surface or bottom
edge. This excess paint can prevent the trim from
sitting tightly against the wall. |
|
 |
This is the MDF (medium density fiberboard)
base board that I bought at Home Depot. This
classic-style baseboard is about 5-1/4" tall. |
|
Estimating Baseboard Quantity:
It's easy to under-estimate
the amount of trim needed for a job. When planning this
project, I measured the length of each wall and made
a list of the required lengths. I always add a
couple of inches to each length, to allow for waste.
One way of estimating materials is to simply add up the
lengths of all the walls and buy 5 to 10 per cent extra.
But... that method can create problems as the project
nears completion and you have a dozen short pieces of
trim that need to span the length of a long wall.
I prefer to examine the list of required lengths and
find several pieces that can be cut from each "stick" of
trim. This works well with MDF trim, which is available
in specific lengths, such as 12 or 18 feet.
But solid wood trim is often available in random
lengths. Sometimes I'll go to the store with my list of
wall lengths, and I will pick out pieces of trim that
are a few inches longer than the dimensions on my list,
or I will figure out 2 or 3 lengths that can be obtained
from one long piece of wood. My
method gives me a load of baseboard where each piece is
"dedicated" to one or more walls in the room. Even with
my dedicated material, I usually buy one or two extra
pieces, because I inevitably make a few mistakes. |
|
| I used a stud
finder to locate the framing, then I marked each
stud location with a piece of blue masking tape.
Previously,
I had marked the stud locations on the subfloor,
but I forgot to transfer the marks to the walls
before I installed the hardwood flooring, so
they got covered over. Oops! |
 |
|
 |
The first piece of baseboard will be installed
like this... but it's not ready yet. |
|
| Note how I
cut the left end with a 45-degree bevel. This is
for the overlapping "scarf joint" that I will
use when the next piece is installed. |
 |
|
 |
A Problem:
There was a large gap below the baseboard,
just a few inches from the right-hand end.
This is caused by a slight upward rise in
the subfloor, between the last two floor joists at
the side of the house. |
|
| To solve this
problem, I needed to remove some material from the
bottom corner of the baseboard. I placed a
pencil in the floor and slid it sideways across
the floor to mark an approximate cut line
on the baseboard. |
 |
|
Since my pencil line did actually
intersect the bottom edge of the baseboard (about 6
inches from the end), I could cut along the line. If the
pencil line stayed above the bottom of the board, I
could either switch to a skinnier pencil or just cut
slightly below the line.
 |
I cut the bottom corner of the trim with a jig
saw. Note that I applied some masking tape to
the base of the jig saw, to avoid scratching
the painted baseboard.
Then I sanded the cut smooth. |
|
However, while cutting this MDF
baseboard, the jig saw blade chipped the edge of the trim
next to the cut. This problem usually doesn't happen when
cutting trim made of regular wood. This "tear-out"
could be prevented by cutting from the back side, but that
requires transferring the cut line, which is not simple
unless the line is straight. Tear-out could also be avoided
while cutting from the front but using a jig saw blade that
cuts on the down-stroke, but using those blades is
difficult because the saw jumps around badly.
Sometimes this tear-out problem can be
avoided by first making a cut along the line with a sharp knife,
then cutting with the jig saw. (I should have done that...)
| Once the
piece of baseboard was cut to my satisfaction, I
fastened it to the wall with a nail gun and 2"
finish nails. I drove 2 nails per stud. I
avoided nailing in the contoured part of the
trim, because it's easier to fill the nail holes
on the flat sections. |
 |
|
However, if the top edge of the base
won't stay against the wall, I will drive nails through the
contoured part.
Installing Carpet?
If the room will be carpeted
later, spacers should be placed under the baseboard
during installation to create a gap that the carpet can
be tucked into. The thickness of the carpet will
determine the spacer thickness, but a common spacer
thickness I've seen used is 3/8 inch, or just scraps of
baseboard (which is often about 3/8" thick). |
|
Connecting Pieces Of Baseboard With A
Scarf Joint:
 |
(Looking straight down) The best way to join
sections of trim along a wall is to employ a
scarf joint, where the each piece is cut on a
bevel.
I made my bevel cuts at a 45 degree angle,
but scarf joints can be made at any angle.
Sometimes I use a 30-degree bevel for scarf
joint.
|
|
| Since the
floor was uneven, my scarf joint wasn't
perfectly tight... it was open at the bottom
(red arrow).
I have two options here... I could re-cut the
beveled end so the miter angle was just off
zero, or I could fill the joint with putty when
I fill the nail holes. I chose putty. |
 |
|
 |
To keep the scarf joint from opening up, I used my
micro-pinner to drive short thin nails through
the scarf joint. Some carpenters apply wood
glue to these joints, especially when one of the
pieces of trim is very short and can't be
fastened in many places. |
|
Coped Ends Make The Best Inside Corner
Joints:
 |
For the next piece of baseboard, I made a
cope-cut on the end. A coped end has a
shape that matches the profile of the
board adjacent to that end.
Cutting coped ends only looks difficult. All
you need is a miter saw, an inexpensive coping
saw, and a few coarse files.
Click Here to read about cutting coped ends. |
|
| However...
since I had chopped some material from the
bottom corner of the first piece, the next piece
sat too high. |
 |
|
 |
So I ripped the base board about 1/8" narrower
on my table saw. Then I had to file away some
material from the bottom to make the trim sit
low enough so the tops of the boards lined up. After I nailed
the base to the wall it looked good. |
|
Mitered Inside Corners Are
Inferior:
Many do-it-yourselfers may be
tempted to simply cut their baseboard at a 45-degree
angle and nail it to the wall.
But it just isn't that easy.
Look at this example:
 |
I nailed these two pieces of baseboard to the
wall with 45-degree miter-cut ends. From several feet
away, a gap is clearly visible. |
| When viewed
from above, the gap is even more
obvious. Note how the back surfaces of both of
these boards are rounded slightly. Before
installing these pieces of trim, I sanded some
material off the backs to compensate for the
radius of the drywalled inside corner. Otherwise
the gap could've been even bigger. |
 |
Why does this gap appear?
Very few walls are perfectly
smooth, flat and plumb. These walls may lean slightly,
which causes the top edges of the baseboard to lean away
from each other, causing the gap to form.
With small trim profiles, these
gaps may be minor. But with wider trim,
especially tall baseboard, gaps on mitered inside
corners can get very ugly. It may be tempting to just
cover these gaps with caulk, but the corner won't look
good and there's a serious chance the gap will open up
over time.
The best approach is to use
coped cuts on one of the boards at each inside
corner.
Why Coped Cuts Make Better
Inside Corners:
| When looking
along the coped piece of trim, the end gap is not
visible at all. |
 |
 |
But when the joint is viewed face-on, the gap
is visible. While any gap can be filled with
caulk and painted, trim always looks better when
cope cuts are used instead of mitered cuts. |
Of course, this leads to another
issue... the order of installation needs to be
planned before the trim is installed. This is simple,
however... you just stand in the room and visualize how
the joints will be seen by people walking into the room.
The cuts are
planned so a person entering the room will be looking
along the coped pieces of trim (i.e. the square-cut trim
is always placed behind the cope-cut trim,
from the viewer's perspective.) This isn't a perfect
scheme... sometimes it will be possible to look along
the non-coped trim and see the gap.
Click Here
to read about cutting coped ends. |
|
Installing Baseboard On Outside Corners:
| Next, I
turned my attention to the pony wall around the
stairwell. There are 3 outside corners here. |
 |
|
 |
This stub wall will require two short pieces of
baseboard. I've been saving the small off-cuts
for this purpose. |
|
A Problem With Most
Drywalled
Outside Corners:
Note the gap between the wall and the
T-square (red arrow). There is no gap right at the
corner. Most outside corners have a "high
spot". The drywall corner bead stands off the
wall by about 1/8 inch, so there is a buildup of
material near the corner. Consequently the miter
cuts on the baseboard will not be exactly 45
degrees. |
 |
|
First I cut two pieces at a 45-degree miter
(using the bevel feature on my miter saw). After a
quick test fitting, I
realized that the joint was open slightly at the back, so I re-cut
both pieces at a slightly greater angle (about 45½ degrees, in this
case).
 |
Once I got a tight-fitting corner joint, I
carefully positioned both pieces and nailed one
piece to the wall. (The right-hand piece still
needs to be cut to an exact length at the other
end.) |
|
| Since my
piece of baseboard wasn't long enough to reach
the corner, I had to finish the run with a small
piece, using a scarf joint. |
 |
|
Trim With Multiple Complex Cuts:
 |
When cutting a piece of baseboard such as this
small piece on the stub wall, I first made the
cope cut and adjusted it until it fit well.
Then I held it in place and marked the back side
where it met the end of the stub wall. |
|
| Next, I made a
45-degree miter cut on the other end, but I
deliberately cut the piece too long. |
 |
|
It's easy to cut the trim shorter,
but I have yet to invent a board stretcher to fix
wood that is cut too short. I sometimes cut a fussy piece of
trim 3 or 4 times, each time getting slightly closer to the
required length, before arriving at the perfect dimensions.
 |
After making a few cuts, these two pieces were
the proper length. |
|
| I decided to
make a "return" on the left end of this piece. I
made another miter cut on that left end. |
 |
|
 |
I cut a small return piece from a scrap of
baseboard. I glued this tiny piece to the left
end of the board mentioned above, and I secured
it with some 1/2" micro-pins. |
|
| When the glue
was dry on the return, I glued the front piece
to the side piece and fastened them with micro-pins.
When I'm installing small pieces of trim, I
often glue and nail them together first. Once
the glue dries (in about an hour) I can use a
belt sander to grind down the back surfaces to
make the assembly fit perfectly. |
 |
|
 |
Then I nailed the assembly to the wall with 2"
finish nails. Unfortunately the mitered gap
opened up, because it should've been mitered at
an angle greater than 45 degrees. Later I can fill
this gap with putty. |
|
Carry On...
| Then I went
back to the outside corner where I started installing
baseboard. I cut the right-hand end of this
piece of base until it matched the mitered end
of the loose piece around the corner (arrow).
These miter cuts were about 46 degrees. |
 |
|
 |
I encountered this hassle...
the lower part of the next piece of baseboard
was sticking out. |
|
This was caused by two problems:
First, the previous piece of trim was just a tiny bit too
short. As I nailed the trim to the wall it conformed to the
curved contour of the wall and drew away from the corner by
about 1/32". Since that short wall has drywall corner beads
at each end, both ends of the wall protrude outward
slightly, which makes the entire wall appear curved.
The second problem was that the wall behind
this next piece of trim had some buildup of drywall mud near the
corner, and this made the wall bulge out just above the floor.
Did I mention that there can be a ton of
problems when doing trim? This is especially true when trying to
make the woodwork look flawless. Maybe I'm too much of a
perfectionist.
| So I marked
the next piece of baseboard on the back side, at the
bottom (red arrow). I used a belt sander to grind away this
excess material. |
 |
|
 |
After grinding away some material from the back,
I installed the baseboard. It fit well and was
standing straight up, not leaning at an angle. |
|
Make It Fit Tight:
When installing a piece of baseboard that is
long enough to span between two corners, I
normally cut the trim just slightly longer
than necessary, perhaps 1/16" or less.
I place one end of the board in a corner.
Then I flex the board so it bows outward
slightly, and force the other end into its
corner.
By pushing the middle of the board against
the wall, the ends will be pushed tightly into
the corners. Then I fasten the baseboard at the
middle and work towards the ends. |
Both ends of this piece of baseboard
are square-cut.
|
|
A Tip For Tight-Fitting Square-Cut
Baseboard Ends:
 |
When installing baseboard with square-cut ends,
the back corner often won't sit tight against
the wall because there is a slight radius to
drywalled inside corners. |
|
| To make the
baseboard sit tight against the wall, I grind a
small radius on the back edge of the baseboard
with a rasp or file. |
 |
|
Touch-Up After Installing Trim:
| After the
baseboard installation was complete, I applied
wood putty to all the nail holes and the gaps at
the outside corners. |
 |
|
 |
I caulked the larger gaps along the top of
the baseboard, and also the gaps at the coped
inside corners. |
|
| After the
putty and caulking was done, I applied masking tape
where necessary and painted the trim again. This
gave the trim a
clean, seamless appearance.
Read more about touching up pre-painted trim after installation. |
 |
|
The Finished Baseboard Project:
 |
The original trim in the upstairs of this 1960's
house was plain, boring "modern baseboard". |
|
| I much prefer
the subtle details of this 5¼ inch traditional
baseboard. |
 |
|
An Extra Step:
 |
When
installing baseboard in a room with hardwood
flooring, it's common to have gaps below the
base caused by waviness in the flooring. |
|
|
Sometimes I will install a shoe moulding at the
bottom of the baseboard. I always nail the shoe
moulding to the baseboard, not the floor.
I
normally just miter-cut the inside corners on
shoe molding (instead of cutting coped ends), because it's easier and adjusting
the cut to fix small gaps is no big deal.
|
 |
|
Notes About Installing Stained
Trim:
Whenever I do a stain-grade trim
job, I apply the stain and urethane before cutting and
installing the trim. The installation of stained trim is
similar to the project shown here, with the following
exceptions:
-
After the trim is installed,
there is no more finishing required except for
touching up the nail holes and some cut ends.
-
Depending on the color of
the wood, nail holes might need to be filled with a
color-matched wax crayon (Minwax sells these,
for example). Sometimes all that is needed is to
apply a felt-tipped stain marker (Minwax
sells these too) to the nail holes and cut ends so
the unstained wood fibers get colored. I've found
this necessary for dark-stained wood.
-
There is usually no need to
fill any gaps at the corners or along the tops of
baseboards.
|
|
More Info:
|
|
|
- Basic
Carpentry Tools
- Miter Saw
- Finish Nail Gun and Air Compressor
- Jig Saw
- Coping Saw
- Files: Round, Triangle, Flat
- Belt Sander
- Micro-Pinner (Optional)
|
Materials Used:
- Baseboard, Colonial, 5¼"
- Finish Nails,
2 Inch, 16 Gauge
- Masking Tape
- Carpenter's Glue
|
|
|
|
|
|
|
|
|
|
|
|
|
