by
George Neuwirt
I run a custom home building company in New England; we've
framed a lot of interesting projects over the years. After
reading a recent article in JLC on framing rake walls (9/06), I
wanted to share a method we use for framing gable
overhangs.
Like the author of the earlier article, we frame the overhang
before lifting the wall. We used to do this the conventional
way, scabbing short outlook rafters to a gable rafter
positioned on top of the gable-wall top plate. But there was a
tendency for the gable rafter to peel off or for the overhang
to sag when we lifted the wall. So about 10 years ago we
adopted a new method, which we've used ever since.
We found that it makes for a much stronger assembly if we leave
out the top plate and instead notch the studs directly around
the gable rafter (see illustration, above). We nail off the
studs through the face of the rafter and add the sheathing, and
we have a rugged wall with solid backing for the ladder.
Another advantage to this detail is that it's easy to add a
nailer on the inside when we have a cathedral ceiling.
George Neuwirt runs a custom home building and
remodeling business in Sunapee, N.H.
On Site With Durisol
by
Alpheus Fair
Last year, we had the opportunity to work with a foundation
material called Durisol while building an addition in suburban
Maryland. Although this product (866/801-0999,
www.durisol.com) has been around for years,
it was new to us — introduced, actually, by the client,
who liked that it's made from recycled and renewable materials
and is nontoxic to the environment.
Similar in some ways to ICFs, Durisol blocks are made from
mineralized wood chips bonded under pressure with portland
cement. They have good R-value when ordered with insulation
inserts, and come in a variety of widths and lengths. We used
12-inch-by-24-inch block with a 1.5-inch mineral-wool
insert.
The blocks were shipped on standard 4-foot-by-4-foot pallets
(1) directly from the factory in Canada to my job site; they
arrived about four weeks after I placed the order. We had to
rent a forklift to place the material curbside, which took
about four hours.
The product retains many of the characteristics of its wood
component; you can cut, screw, glue, and nail it with
conventional tools. One inexpensive carbide-tipped blade in my
71/4-inch circular saw lasted me the entire job (2). When the
depth of cut exceeded the capacity of my circular saw, we used
a reciprocating saw with a masonry bit (3).
The top course of block had to be cut down 3 inches to make
necessary grade. To ensure a consistent cut, we clamped a
straightedge to the saw (4).
Whenever we cut from the exterior side of the block, we were
careful to adjust the blade depth so as not to cut the
mineral-wool insulation insert. After cutting through the
cementitious exterior, we would go back through the saw kerf
with a hacksaw blade mounted in a simple straight plastic
handle to cut the insulation (5).
To create a bond beam across the top course, we first kerfed
the block webs (6), then tapped lightly with a hammer to remove
the material (7, 8).
We used a pump truck to place the concrete (9), following the
manufacturer's recommended concrete specifications: 2,500 psi @
28 days, minimum slump of 7 inches, aggregate not to exceed 3/8
inch. We began placement at window openings to prevent any
voids as the rest of the wall was poured.
Once the area below the windows was filled, we slowly filled
the wall cavity, starting at least 3 feet from corners and
taking care not to exceed a vertical height of 4 feet per hour,
again per the manufacturer's specs.
Since Durisol isn't structural, we had to place the 2x6 wall
for the addition directly above the concrete core, creating a
4-inch ledge on the outside. We dealt with this by installing
copper flashing with a drip cap along the top of the foundation
wall, then allowed the stucco finish on the 2x6 wall to bell
out slightly to get a pleasing finished look (10, 11).
1011
Alpheus Fair owns and operates Fair Carpentry, a
custom-build firm in Takoma Park, Md.