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From Out of the Caves
From the
time our ancestors first decided that caves were too cold and drafty
they began to build shelters with a commodity that was readily
available to them: wood. This was especially prevalent in the
northern climates where trees were readily available. Structures were
sometimes large dwellings where large families lived together for
safety and warmth and to support the walls and roofs required the
invention of a skeleton or framework. The early pioneers are depicted
as builders of log cabins but even these structures gave way to the
wood-framed systems that are a mainstay today.
A home frame, in essence, are like
the frame of a box kite. It forms the strength of the structure
and provides the surface from which the other essential parts of the
home will be placed. These are the main functions of a house frame:
Supports the entire house down to the
foundation.
Provides a platform and surface area for the
protective parts of the home: roof, siding, windows.
Types of Frames
Wood
Although in North America other materials are
prevalent and, in some cases are gaining considerable ground in home
construction, wood is still the leader in framing. Today's
building codes usually require a 2” X 6” boards. A wooden
wall is made up of three parts:
Studs: These are the vertical parts of
the frame and, in most cases, are 8 feet high. Studs are usually
place 16” apart for a strong wall.
The Top Plate: This is made up of two
(2) horizontal 2X6's that attach the studs on the top. The second
one is used for strength
Sill Plates: This is usually on 2 X 6
which holds the bottom of the studs in place. Sill plates attach to
joists, the horizontal boards which sit on the foundation and form
the floor.
The walls are raised up after the joists have been
secured on the foundation and the floor boards have been put down.
The floor acts as a level place to build the walls by attaching
the plates and studs. Once attached the whole wall is raised up
and anchored into place until the other three wall have been raised.
Then the walls are attached to each other and the second set of
boards are secured to the single top plate to add reinforcement to
the wall.
One of the most important items in successful
framing is keeping the parts of the wall accurate and level. All
the other parts of the home building process – drywalling,
siding, cabinets and finishing work – will be severely affected
if accuracy is in any way compromised.
The roof trusses are attached to the top plate
and held in place with the roof sheathing, which is usually plywood
or Oriented Strand Board – OSB. The better roofs use tongue-and
groove planking. Most building codes require the roof trusses to
be pre-manufactured to rigid specifications but they can be
constructed on site. The pitch of the roof is decided by the
architect who designed the plans and takes into account the climate
and loads – e.g. Snow – that will be placed on the roof.
Steel
During the last millennium the European countries
denuded their forests and wood-framed homes gave way to brick and
stone, because that was material available to them. Although North
America still has a thriving lumber industry the availability of
economical building supplies is slowly dwindling and builders here
are looking elsewhere. One of the materials which is growing in
popularity is steel.
Although it sounds heavy steel studs are
actually very light because their shaping makes them strong. They
are made from light-gauge, galvanized steel that makes them lighter
than wood and, in many cases, cheaper as well. Steel also comes in
many lengths and can be fastened together with as few tools as a
drill with a screw bit and a pair of sheet metal cutters, or
tinsnips. So you don't need a chopsaw for cutting ends and a jigsaw
to cut holes. Why? Because the studs can be purchased in many lengths
and widths and the holes for conduit and pipe are stamped out. And,
using a laser for sighting, the wall can be a straight as an arrow in
far less time that it takes to adjust wooden studs.
More builders in the hurricane-prone areas are
starting to use it for framing new houses. In addition to the
strength and lightness steel studs are termite-proof, rot-proof and
mold-proof. The studs are also pre-stamped for electrical conduit
and most plumbing. The only drawback is that steel, even galvanized
steel, must be kept dry and it is not recommend for basements where
moisture could be a concern.
Aluminum
Aluminum tube-framed homes are a fairly new
innovation and definitely curb the corrosion problem that may plague
steel. It is extremely lightweight but is very expensive right now.
Aluminum frames, however, are ushering in a new era of homes
which use aluminum as the outer skin, in much the same way way as
Airstream trailers. By using thses new architectural forms the old
platform framing methods can be scrapped in favor of new techniques.
As well, the curved, aluminum surfaces can be conformed to the
weather patterns letting the turbulence flow around the dwelling much
like an aircraft fuselage.
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