DIY

Expand Your Living Space by Removing Walls

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ILLUSTRATION: DON OSBY
Diagram: Typical wall with new header.

How to expand your living space using subtraction, not addition by removing walls from your home’s structure.

Expand Your Living Space by Removing Walls

Walls might be unwanted for any one of several reasons. For
one owner, a room, hallway or closet might comfortably be
sacrificed in the quest for an open floor plan. For
another, an existing doorway could easily give way to a
full-fledged entrance. And should the search for space go
beyond the house into a finished garage or porch, a wall
will have to be opened somewhere to provide access.

If the thought sounds intimidating, that’s probably because
it should be. Most walls are significant to a
home’s structural integrity, and removing walls without
providing an appropriate substitute is a standing
invitation to worry. Fortunately, there are standard
methods for safely spanning just about any opening, and
most involve nothing more than a willingness to understand
basic framing carpentry.

Removing Walls: The Way of the Wall

For our purposes, walls come in two varieties: bearing and
nonbearing. The first, and most important, transfer live
loads (the weight of people, furniture and snow) and dead
loads (the weight of a building’s construction materials)
vertically downward to the structure’s foundation and
footings. The second type is merely a partition that
supports no load other than its own weight. Nonbearing
walls are of little significance if your home is
structurally sound.

Typically, a bearing wall looks like the “before” version
of our main illustration. At the base, it’s supported by
rows of horizontal floor joists running at right angles to
its length. Those joists in turn rest on either a girder or
a masonry foundation wall. The upper surface of the joists
is covered with plank or plywood subflooring, and the wall
rests upon that. It consists of a single soleplate, a
series of vertical studs placed 16 inches on center (24 inches for 2 by
6s) and a double top plate. The joists for the second floor
or ceiling above are nailed to the top plate over each
stud.

Before thinking about actually removing a wall, it’s
essential that you assess the structure’s framing. Get your
hands on some old clothes and a 25 foot locking tape measure,
and begin your inspection in the basement or crawlspace.
Determine and record the location of interior foundation
walls, or the equivalent girders and supporting piers or
posts. It’s likely that the pattern for the basement is
duplicated in the stories above. To be sure, measure the
position of the first-floor walls, and compare that of the
second-floor walls as well.

If you simply have attic storage above the first floor,
look for a central girder (doubled two-bys with joists
extending from both sides at a perpendicular) and establish
whether it’s supported only at its ends or from beneath its
midpoint too. Generally, a beam longer than a dozen feet or
so needs some help from below. Should your attic space be a
trussed system (easily identified by a V or W pattern of
boards connecting the joists and roof rafters), it’s most
likely supported by two outside walls and doesn’t bear on
any interior partitions.

Walls vertically in line with each other and a foundation
member can be assumed to support weight, but even walls
parallel to and within 5 feet or 6 feet of them may share that
load. Another clue to the presence of a bearing wall is
that the joists above it are too small or spaced too far
apart to span any distance without support. Nonbearing
walls, on the other hand, often run parallel to joists, and
though they may not meet code–sometimes have studs
spaced at distances greater than 16 inches on center.

Ultimately, any appraisal on your part should consider the
requirements of your local residential building code, both
as a clue to how the structure may have been put together
and as a guide to how it should be modified. The code
handbook (available through your county building inspector)
outlines approved techniques and specifies span and load
limits, among other things. If unanswered questions
persist, or if you’re not quite ready to remove wall
sheathing to get a better look at what you’re up against,
consult a structural engineer. His or her opinion will be
well worth the small investment, particularly if you’re
considering a span greater than 12 feet or if multiple stories
are involved.

Unshrouding the Mystery

You’ve studied your particular situation thoroughly, and
you’re certain that the section of wall you want to remove
is carrying the weight of the floor above. To take care of
that load, you’ll need to replace the wall with a header,
or lintel, that itself is held up at its ends on posts.
It’s nothing more than a sturdy beam–usually deeper
than it is thick–which allows a clear span across an
opening.

Headers can be complicated trusses or expensive steel
I-beams, but for most purposes, two appropriately sized
pieces of dimension lumber fastened around a core layer of
1/2 inch plywood will be perfectly adequate.

An engineer would rely upon a formidable round of
calculations to determine the proper size of a header, but
to save you that trouble we’ve worked up a reference chart
which simplifies matters immensely. It takes into account
the allowable loads for the three most common sizes of
lumber headers and states their length limits, based upon
whether the house has one or two stories, or two stories
with full attic storage or a third floor.

Clearly, you’re not going to know exactly how long to make
the header until you’ve stripped away the wall’s finish
surface and can see the internal framing. In preparation
for this, you’ll need some standard carpentry tools
(including a framing hammer, a tape measure, butt and cold
chisels, a utility knife, a flat pry bar, a level, pliers
with side cutters, a dry-wall saw and a drill with
extension bits) and a few heavier implements such as a
circular saw, a wrecking bar and a hand sledge. You’ll also
want an inexpensive circuit tester, safety glasses, a dust
mask, at least a few 4 inch clamps and (you can rent this) a
reciprocating saw with wood- and metal-cutting blades.

You can try to keep the mess to a minimum, but that will
probably be an exercise doomed to failure. Just use a drop
cloth if you have one, and keep the sharp edges of tools
off the floor . . . you’ll appreciate your foresight when
the job’s done. Begin at the breaker box by shutting off
power to all the receptacles in the wall you’re working on,
then double-checking them with the circuit tester. Chances
are you won’t be removing a wall with plumbing in it, but
turn the water supply off and plan to work slowly on your
first saw cut just in case. Using the flat bar, carefully
remove and save the ceiling and baseboard trim and any
other molding around doors, etc.

Next, mark off in pencil
the rough area you plan to do away with. Because wall studs
are usually placed 16 inches apart, it’s best to measure inward
from the corners in multiples of that distance so you’ll
know where to terminate the opening. Nailhead dimples or
cracked plaster seams are even better indicators of stud
location if you can spot them. On the other hand, it may be
easier to simply remove all the wall sheathing and replace
it as needed later. The material costs involved won’t be
that much greater, and this method gives you the advantage
of not having to struggle to spare something that may get
damaged anyway.

Start at a point near the top of the wall and drill an
exploratory hole into the wall cavity, then use your saw
to cut halfway down through the sheathing. Repeat this
process 9 inches or so to the inside of your first cut, then
slice horizontally through the top and bottom points so you
can remove a rectangular wall section. Don’t try to cut
through both sides of the wall at once; all you’re after is
an access from which you can get a clear view to the
soleplate inside the wall. In older buildings, you may
encounter fire stops–wooden blocking nailed more or
less horizontally between studs. If that’s the case, cut
into the wall again just below the blocks, but don’t go all
the way to the floor . . . just remove enough material to
get a peek at what’s inside.

Your caution is to prevent you from cutting through the
unknown wire. But once you can see to unsheathe a stud
cavity safely from ceiling to floor, you’ll be aware of any
horizontal wiring and will only have to be careful of cable
coming up through the soleplate, which most likely will
terminate at a nearby receptacle. At this point, you can
use your utility knife to slice through any seam or fill
that might inhibit a clean separation at the joint between
the wall and ceiling. Continue removing the wallboard with
care until you’ve reached your marked limits, then strip
the wall from the opposite side. (The job will be easier if
you drill through the back of the sheathing at the corners
so you can pencil an accurate cut line.) With the framing
exposed, you’re ready to prepare the header.

Visible Means of Support

Since the wall studs are already in place, it’s simplest to
choose two of them to define where the header will
terminate. Each lintel end must bear upon at least 3-1/2  inches
of support surface, so it’s quite convenient to double up
some of the 2 by 4s you’re removing and fasten them to the
flanking studs to serve as posts. One caution: With some
types of construction, the posts may not rest directly over
a joist, so you’ll have to plan on shifting them slightly
to one side so they will. If that’s impractical, you’ll have to block the space between the floor joists from below, thus using the girder beneath the joists for support.

Once you know how long to make the header, purchase the
straightest No. 1 grade structural lumber you can find, as
well as a sheet of 1/2 inch B- or C-grade exterior plywood. Cut
the plywood core to match the depth of your two-bys,
locating the butt joint nearer one end if the lintel is
over 8 feet in length. Apply a crosshatch pattern of
construction adhesive to all mating surfaces, then clamp
the boards around the plywood. Finish the job by nailing
the assembly together from both sides with 16d common
nails.

At this point, you’ll need to determine how best to shore
up the ceiling while you work on cutting out the wall
studs. For the sake of convenience, it’s easiest to shore
just one side of the wall, and for single- or two-story
homes, that will probably suffice. However, if there are
two floors above the one you’re working on, or if the
joists of the floor above the wall aren’t nailed together
where they overlap (or if they’re not fastened to the
wall’s top plate at all), you’ll have to shore the ceiling
about 2 feet from both sides of the wall–and remember
that you’ll need room to get the header in place somehow.

The shoring framework can be made from 4 by 4 posts with 2 by
6 or greater plates across the top and bottom. Though the
strength of the shoring depends on the weight above, a post
every 4 feet or 5 feet should be more than sufficient, and you can
always bolster the frame with internal 2 by 4 studs or a
diagonal brace nailed between the corners. Ideally, you
should be able to use your shoring frame as a “kicker,”
building it slightly taller than the ceiling is high so it
can be driven into place from the floor, raising the joists
above just enough to set the header correctly.

A strip of carpet placed underneath the lower shoring plate
will ease this procedure. Should you have to use small
hydraulic or screw jacks to place the shoring, set them on
2 feet-long 4 by 4 pads positioned over adjoining floor joists,
then use 4 by 4s with short top plates as jacking posts.
Make certain they’re perfectly plumb before you apply any
pressure, and don’t raise the ceiling more than 3/4 inches over
level unless you bolster the floor from below. Temporary
supports have a way of walking sideways under pressure, so
check their position often.

The Last Stand

There are a number of ways to install a header, and each
has its own merit. The dictates of your building code may
set the precedent, but if there’s no specific guidance,
plan on placing longer lintels–say over 5 feet or
so–directly against the wall’s top plate, and shorter
ones the established distance below the plate (see
illustration), filling the gap with short 2 by 4 cripple
studs. If you need to make up only an inch or so, trim out
the header at the bottom with scrap wood.

Begin by cutting the existing studs at the center, then
prying each end free. If you want to reuse the studs, cut
them as close to the bottom as you can without hitting the
toenails. Merely sledging the boards of the plate will
splinter their ends and make them unusable.

Once the uprights are out, use a circular saw set at a 1-1/2 inch depth to cut through the soleplate exactly 3 inches in from
each standing flank stud. Pry the soleplate off the floor
with a wrecking bar, then cut or remove any exposed nails
from the top plate. After double checking the correct
length of the stud support posts, fasten the outside set to
the flank studs with 16d nails, and the inside set to those
you just installed, making sure the posts are plumb all
around and the lower ends are toenailed into the sole
plate.

Before placing the header, remeasure the total span
distance and trim the beam’s length so there’s a fraction
of an inch of free play at one end for fitting. If there’s
any notching or edge-shaving to be done, now’s the time to
do it. Then, with the help of a couple of friends, lift the
header to the posts, position it, and nail it to both the
flank studs and the supports below. If you’re using cripple
studs, cut them to length (don’t forget that your ceiling
is probably a bit higher than it should be), and nail them
between the top plate and the header at 16 inches on center.
Otherwise, nail the header to the plate to keep it from
migrating. Should you need to reroute a wire, it can pass
through 5/8 inch holes in the cripples or run below the floor
joists in the basement. Don’t try to squeeze it between the
planks of the lintel, or it may get damaged.

Buttoning Up

With everything securely in place, you can gradually remove
the shoring and allow the house to settle comfortably on
its new framing. Because it’s wise to give the members a
few days to stabilize to their environment, you can use the
time to patch the floor where the soleplate was. Since the
plate was probably set on the subflooring, you may only
have to match the existing underlayment beneath carpeting
or vinyl and piece in the appropriate surface patches. Wood
flooring repair is more complicated, but it also is a
matter of mating pieces to the original flooring and
achieving the same finish height.

Covering the header framing is actually somewhat simpler.
Because the lintel is the same thickness as the original
wall frame, it shouldn’t be difficult to cut sections of
standard wallboard to fit against the undamaged sheathing.
Trim the edges of the old board if you hadn’t already, then
fasten the newly trimmed patches in place around the posts
and header with dry-wall nails. Tape and fill the seams,
patch the nail dimples, and paint or cover the surface to
match the other walls.

It’s probably naive to assume that every wall remodeling
job will proceed as smoothly as the one described here. But
if you keep in mind that more than half the work is in
planning what to do, doing it right should follow
naturally.