QMNC A Installation Guide
Sources: Uniform Building Code; American Wood Council, NDS 2005, Table 11.2 A, 11.3.2 A
Notes:
1) Thread must be embedded in a rafter or other structural roof member.
2) See IBC for required edge distances.
**Note: To maintain waterproong it is important that the aluminum ashing is properly placed under one full course above the mounting block with at least some of the ashing extending
up under the course above that as well. See instructions on back.
Lag pull-out (withdrawal) capacities (lbs) in typical lumber:
Lag Bolt Specications
Specic Gravity 5/16" shaft per 3" thread depth 5/16" shaft per 1" thread depth
Douglas Fir, Larch .50 1330 266
Douglas Fir, South .46 1175 235
Engelmann Spruce, Lodgepole Pine (MSR 1650 f & higher) .46 1175 235
Hem, Fir .43 1060 212
Hem, Fir (North) .46 1175 235
Southern Pine .55 1535 307
Spruce, Pine, Fir .42 1025 205
Spruce, Pine, Fir (E of 2 million psi and higher grades of MSR and MEL) .50 1330 266
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