Structure material - Engineering Class Home Pages

Wood
Types:
• Balloon framing (rare)
• Platform framing
• Heavy timber framing
Advantages:
• The only renewable material
• Warm, natural appearance
• Low energy required
• Easy to work
• Low cost
Challenges:
• Combustible
• Termite attacks
• Decays in variable humidity
• Limited height and floor area
Material Copyright Prof Schierle 2011 4
Platform framing
Platform framing is used for low-rise residential
structures, due to economy & flexibility. 2x4 studs
@ 16” reach from platform to platform. Double
top plates overlap at corners and splices. Plywood
sheathing, nailed to studs, resists lateral wind and
seismic loads. Joists, usually 2x12 @ 16” support
plywood floor and roof (platforms). Blocking
resists joist buckling and supports plywood panel
edges to transfer shear. Standard plywood and
gypsum board panels 48” (4’) wide match 2, 3, or 4
joist/stud spaces of 24”, 16” or 12”, respectively.
A Joists, 2x12 or 2x10 @ 16", 24“, or 12” o.c..
B Blocking
C Double top plates overlap at corners and splices
D Studs, 2x4, 2x6, or 3x4 @ 16“ or 24” o. c.
E Bottom plates
F Double plates supporting joists
G Anchor bolt, 1/2“ @ 4‘ o. c.
H Sole plate, min. 6" above soil
I Concrete foundation
Maximum height: 3 stories (4 with fire sprinklers)
Material Copyright Prof Schierle 2011 5
Wall erection
Plywood shear wall resists
lateral wind and seismic loads
Woodframe house
Material Copyright Prof Schierle 2011 6
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