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Printreading for Residential and Light Commercial Construction
the upper side of stressed-skin panels is thicker than plywood on the lower side. Insulation may be placed inside the panels. Ventilation holes are drilled in the 2 × 4s for air circulation. Stressedskin panels are primarily used to span wide distances between supports. Balloon Framing
Wood Truss Council of America
Prefabricated components, such as roof trusses, are commonly specified for residential and light commercial buildings.
A stressed-skin panel is a structural unit used in floor, wall, and ceiling systems that consists of plywood panels nailed and glued to a wood frame. Typically, stressed-skin panels are framed with 2 × 4s spaced 16″ OC and covered on each side with plywood. See Figure 3-8. Plywood on
VENTILATION HOLES WOOD HEADER
Balloon framing is a multistory framing method in which one-piece studs extend from the sill plate to the double top plate. Upper floor joists are nailed to the sides of the studs and receive additional support from a ribbon board that fits into notches cut into the studs. See Figure 3-9. Wood shrinks primarily across the width of the grain. In balloon framing, wood shrinkage is minimized by using studs that extend from the sill plate to the double top plate. In the past, balloon framing was a popular framing method. However, due to the limited availability and high cost of long wood studs, balloon framing is not as common today. In split-level residences, balloon framing may be used in the central section of the house. Balloon framing provides passageways for ductwork and raceway systems through the open stud spaces from floor to floor. However, the stud spaces can also act as flues, enabling fire to spread quickly, unless fireblocking is installed near the floor levels.
PLYWOOD SPLICE PLATE PLYWOOD TOP SKIN BLANKET INSULATION
WOOD STRINGERS WOOD BLOCKING
VENTILATION OPENINGS PLYWOOD LOWER SKIN WOOD HEADER
Figure 3-8. Stressed-skin panels span wide distances, and are used in floor, wall, and roof systems.