A.Clayton DeKorne responds: Here’s one
method that has worked well for me in the past. After stripping
the siding off the wall in question, lag a ledger into the wall
stud above the existing second-floor level. Then install
temporary T-posts made from 2x6s nailed together at right
angles, as shown in illustration A (next page). We’ve
typically installed posts every two feet or so along the
ledger, depending on the loads. Only one of the 2x6s in each
post bears on the ledger; the other stiffens the bearing 2x6.
Use plenty of nails to hold these 2x6 posts together, so the
two pieces function as one stiff member.
Cut the posts long. Once they are wedged up under the ledger
at a slight angle, we use a sledgehammer to drive the bottom
end of each post toward the building. This lifts the structure
slightly to take the load off the existing wall studs. To keep
the posts from kicking out, screw a block down to hold the end
of each post in place, much in the same way wall bracing is
secured to a floor deck.
Obviously, this method works best if you can install the
addition foundation and floor structure first, so you’re
working off a flat deck. To do this, we typically cut holes
through the wall at the existing floor and ceiling levels, so
we could take whatever measurements and siting necessary to
align the old and new floors and ceilings. This also means the
home is opened up for a shorter time — a good goal to
shoot for if the owners are living in the house while the job
is in progress.
While I’m most comfortable supporting the posts on the
joists of my new work, I have also used this method working off
the exterior grade, using plywood feet on the posts, and stakes
to secure the post ends.
If your bearing wall supports a hip roof, you may not have
to support the interior ceiling joists. But many times, the
joists will intersect your new beam at right angles. In this
case, we post up from the interior floor deck, aligning the
posts over existing floor joists, as shown in illustration B,
Alternative method. Instead of using T-posts
at an angle for the exterior posts, I have seen one contractor
successfully use doubled 2x6 posts installed vertically on
hydraulic bottle jacks. One 2x6 on each post supports the
ledger, while the other 2x6 lapped the face of the ledger
(illustration B). The contractor claims this method gives him
more control lifting the structure and doesn’t require
working off a flat deck. He supports the jacks on wide, level
Making the cut. When you’re ready to cut
the wall out, start by cutting every other stud. If the Sawzall
blade starts to bind, back off. This probably means there is
still some load on the studs. Either beat the ends of the
T-posts closer toward the building with a sledgehammer, or jack
the posts up.
Also, make certain the structure is securely nailed together
before you start cutting. Nail off as much of the exposed
sheathing above the beam as possible to make sure the wall
holds together to spread out any hidden point loads. Unless the
addition will have a flat roof, you will want to strip the
siding well above the existing second-floor level anyway.
Also, make sure you cut out the sheathing to expose the
studs where you will insert the beam before you cut out
the supporting wall. Give yourself plenty of room to maneuver a
Sawzall, so you can get as straight a cut as possible on the
ends of the studs that will bear fully on the new beam.
Inevitably you’ll have to shim these anyway, but
it’s still best to have a square cut for full bearing on
the shim. I usually cut the studs 1/4 inch short, or more, to
allow for any crown in my beam.
Good prep is the key to this kind of demolition. Think every
step through, and do everything you can before you start
cutting the studs loose. Ideally you should be cutting out
individual studs that are free of sheathing and plaster. After
removing all the studs, immediately insert the beam, so the
structure is supported on temporary posts for as short a time
as possible. Nothing will keep you awake more than leaving a
house on temporary supports overnight.
Clayton DeKorne is a senior editor of the Journal of