Last year, our company was hired to remodel the 24-by-30-foot
kitchen ell of a 150-year old Vermont home. The owners wanted
the renovation to retain the house’s vintage look while
addressing some rather serious defects in the structure.
The second-floor living space of the balloon-framed ell was in
good condition and definitely worth saving, as was the
beautiful historic slate roof with fine period trim. The first
floor, though, was in bad shape: Half the joists had previously
been shimmed several inches, creating in effect two separate
floor decks, and the entire floor sagged and bounced. We first
considered removing the framing and pouring a new radiant slab
within the existing stone foundation walls. But on further
investigation, it became clear that this would be at best a
Band-Aid approach. Justifying the kind of investment the
clients wanted to make in their new kitchen would require
replacing the old foundation and first-floor framing.
The next order of business was to remove the siding and plaster
so we could see what condition the framing was in. But before
starting demolition, we established a benchmark elevation on
the ell and transferred it to the barn next to the house. We
figured that the upper floor would drop slightly as we worked,
and we wanted to be able to return it to its original
position.
After removing the finishes and exposing the framing, we
discovered that a previous builder had shimmed the second-story
floor joists to level the floor in the upstairs bedroom over
the kitchen area. While this created a flat floor, it left
almost 4 inches of sag on the bottom of the joists. It was
clear we would have to take pains to create a flat ceiling in
the new kitchen.
A Plan for Supporting the
Roof
How to hold up the second story while building the new
foundation underneath was the big question. We first considered
using steel I-beams supported on timbers stacked outside the
foundation area. We abandoned this idea when the excavator
pointed out how massively tall the cribs would have to be;
plus, we knew they would be a pain to work around. We also
thought about removing and replacing the foundation in short
sections, working our way around the perimeter, but rejected
this as too time-consuming.
Then, in a meeting with the excavator and concrete sub, we came
up with a plan: We would first reinforce the second floor with
a grid of LVL beams supported by steel columns; next, remove
the framing and stone foundation; then form and pour a new
footing and foundation, encapsulating the steel posts in the
concrete.
We calculated the approximate weight of the roof and floor
— the dead load we’d have to support while the new
foundation was built — and had the lumberyard size the
LVLs we would use. The idea was to carry all the second-floor
loads to the exterior walls and from there to the ground with
as few posts as possible. With no temporary shoring to work
around in the middle of the ell, the excavator would have an
easier time digging out the crawlspace. After the new
foundation was placed, we would frame new walls and cut off the
steel columns at the level of the rim joist. The LVL grid would
remain in place to support the new ceiling and would also serve
to reinforce the sagging joists above.
Installing the Ceiling Grid
We located the lowest point of the sagging floor joists and
snapped a line on the inside face of the exterior wall studs at
that elevation. This marked the top of the LVL grid members.
The first piece we installed was a 14-inch LVL beam that runs
across the width of the ell about 12 feet from the gable end
(Figure 1). This LVL was in line with the wall
that would be built later between the new mudroom and kitchen.
For now, we ran the beam long; we would cut it flush later
after supporting it on the new framing. It broke the ceiling
space into two sections, cutting the span of the new ceiling
members on either side. Later, when we framed the mudroom wall,
we would place a post under the beam to transfer the ceiling
and second-floor loads to the new crawlspace girder and on to
the ground.



Figure 1. A new 14-inch LVL beam, inserted below the
existing second-story joists, spans the 24-foot-wide kitchen
ell (top left). Several smaller LVLs run between the beam and a
ledger attached with LedgerLok screws to the main house wall
(top right). Short blocks between the LVLs and the original
floor joists above help to stiffen the floor system (bottom).
We next attached a 9 1/2-inch LVL ledger to the wall of the
main house, using 5-inch LedgerLok screws
(fastenmaster.com,
800/518-3569), which have a structural rating of around 212
pounds per screw in an application like this. Between the
ledger and the beam we hung five 18-foot-long LVLs, placing
them on 6-foot centers. Two of these ran along the eaves walls
and were attached to the studs with two TimberLok screws per
stud. This was a critical connection: When it was time to cut
away the lower part of the existing stud walls, the LVLs
attached to the perimeter studs would act as headers,
transferring all the overhead loads onto the steel posts.
The gable end of the ell was framed a little differently: Here,
we had no perimeter LVLs on the inside, so instead we fastened
long 14-inch beams to the outside of the exposed studs, again
using two or three LedgerLoks per stud (Figure
2). We ran a 9 1/2-inch LVL across the gable end. At
post locations, we added short pieces of LVL on the inside,
sandwiching the studs and creating a stable bearing area for
the column caps.
Figure 2. At the end of the ell and across
the gable, wide LVLs are fastened to the outside face of the
studs to pick up roof and floor loads when the walls are
removed.
Inserting the Steel Columns
We used seven 4-inch-by-4-inch steel columns in all, each with
a 30,000-pound capacity, to pick up the weight of the roof and
second-floor framing. We worked our way from bearing point to
bearing point, removing just enough studs to give us room to
cut out the sill and excavate for a post footing
(Figure 3). At 12 feet, the columns were long
enough that we could place the 6-inch-thick, 16-inch-diameter
precast concrete footings below the bottom of the eventual
stem-wall footings. We placed a column under each end of the
14-inch LVL beam, one at each outside corner and the rest at
intermediate locations. With the exception of the gable-end
support, we placed the columns within the stud cavities so we
could form and pour the footings and foundation around
them.



Figure 3. Working in increments around the
perimeter, the crew removed as few studs as needed to excavate
and install the steel posts (top). At the top, the studs were
cut flush with the LVL ledgers and solid blocks inserted to
provide good bearing for the 6-inch-square post caps (bottom).
The columns had 6-inch-by-6-inch-by-1/2-inch-thick steel plates
welded to each end. As we installed each column, we used 2-by
blocking and LVL cutoffs as necessary between the
column’s top plate and the bearing point on the LVL to
ensure full support. With the steel posts in place, we removed
the rest of the wall framing and the stone foundation and set
about getting the old slab out of the way.
Hidden Problems
Nothing goes exactly as planned in remodeling work. We knew
that there was a buried cistern just outside the existing stone
foundation, and our plan was to remove it and fill in that
area. Unfortunately, we soon discovered that the cistern
— a stubborn structure of reinforced concrete — was
attached to the main house foundation and connected to another
cistern inside the crawlspace. We had no choice but to
jackhammer the obstruction — an unexpected task that
added about 60 percent to the budgeted excavation cost
(Figure 4). The rest of the concrete was
removed with the excavator.
Figure 4. With the walls out of the way, the
excavator carefully removes an existing concrete slab (left);
part of the foundation had to be jackhammered into submission
(right).
Figure 5. The new footings (top left) and
stem walls (top right) were formed and poured around the steel
columns. The foundation and rim joist were carefully insulated
with 2-inch polystyrene (bottom).
Marrying Up
Once excavation was complete, we formed and poured the new
foundation, working around the steel posts (Figure
5). Before framing the deck, we insulated the rim
joist and the inside of the foundation wall with 2-inch-thick
blueboard and covered the dirt floor of the crawlspace with a
vapor barrier, which we sealed to the insulation on the walls
(Figure 6). On the outside, we coated the
concrete with cold asphalt, ran both a perimeter and gutter
drain to daylight, and backfilled with stone.
Figure 6. The posts were left in place until the deck
was framed (top left). As the walls were framed (top right),
each steel post was cut off at the top of the rim joist.
Bottom: the finished kitchen, outside and in.
At this point, we entered the phase of the project that we call
“marry-up.” Working from the new deck, we proceeded
to frame up the three walls needed to close the building in.
First, though, we had to jack up the roof slightly to match the
original benchmark elevation. We then framed the walls in
place, working in short sections around each post. Once we had
sufficient support, we cut each column flush with the rim joist
using a reciprocating saw. (We were able to sell the remnant
steel back to the fabricator, a $700 credit on the original
$2,545 cost.)
The two eaves walls presented a minor challenge. Since we were
installing a kitchen, the walls had to be plumb. Over the
years, the roof had shifted and bowed a bit, so we needed some
fudge room. Fortunately, the 1 1/4-inch-thick frieze board and
1-inch-thick sheathing gave us the space: We were able to keep
the wall plumb, straight, and square on the inside and hide the
changing reveal on the outside.
The gable end was worse. The wall bowed out as much as 5 inches
at the second-floor level. We didn’t have much choice: To
match the bowed wall, we cantilevered the deck in the shape of
an arc so that the wall framing follows the new deck and
marries up at the old gable wall nicely. We then shimmed this
wall plumb on the inside. The owners enjoy showing the bellied
walls to visitors — it’s part of the house’s
historic charm.
After successfully finishing a project like this, it seems we
remodeling contractors are blessed (or is it cursed?) with the
ability to drive by and say, “That wasn’t so
hard.” Maybe it’s because we choose to forget the
challenges a project presented — including the constant
trial of keeping schedule, budget, and quality in balance. But
I think there’s another reason: When we surround
ourselves with skilled crew members and knowledgeable
subcontractors, even the most difficult project is
enjoyable.
Larry Buck co-owns Conner & Buck
Builders, a 20-year-old design-build firm in Bristol,
Vt.