Can we use load modifiers in this case?
Can we use load modifiers in this case?
(OP)
I am checking wind uplift on a light gauge steel framing roof in Southern California. I am seeing ni the cold-formed design software an input for load modifiers, the documentation states:
"Some Building Codes allow loads to be modified for combinations including wind,
seismic or multiple transient loads. Previous versions of LGBEAMER used a simple ‘Wind or
Earthquake’ check box that, if checked, would cause all loads to be multiplied by 0.75 when
checking strength interactions. Newer building codes use a more complex set of rules for load
modification and have eliminated the simple 0.75 factor for load combinations containing wind or
earthquake forces. "
My question is, since this is a load combination for wind, am I allowed to use the 0.75 load modifier on top of the usual ASD load factors? Thanks.
"Some Building Codes allow loads to be modified for combinations including wind,
seismic or multiple transient loads. Previous versions of LGBEAMER used a simple ‘Wind or
Earthquake’ check box that, if checked, would cause all loads to be multiplied by 0.75 when
checking strength interactions. Newer building codes use a more complex set of rules for load
modification and have eliminated the simple 0.75 factor for load combinations containing wind or
earthquake forces. "
My question is, since this is a load combination for wind, am I allowed to use the 0.75 load modifier on top of the usual ASD load factors? Thanks.






RE: Can we use load modifiers in this case?
DaveAtkins
RE: Can we use load modifiers in this case?
Is this a new design or are you load checking an existing construction, because that would also make an impact as to what's applicable as well.
RE: Can we use load modifiers in this case?
RE: Can we use load modifiers in this case?
RE: Can we use load modifiers in this case?
I have never agreed with this line of thinking. If you are checking the capacity of an existing structure, you should check it using today's codes.
DaveAtkins
RE: Can we use load modifiers in this case?
RE: Can we use load modifiers in this case?