My colleague and I are not clear on the snow seismic load as defined in the ASCE 7-16, Ch.12, section 7.2, item number 4, which states that the effective seismic weight includes 20% of the uniform design snow load, when the flat roof snow load Pf, exceeds 30 psf [or minimum Pf as set by jurisdiction having authority]. What is the uniform design snow load (UDSL) in reference to? Internet research seems to imply that the UDSL is interpreted by peers to be the Pf load. Is this the correct interpretation or is the UDSL meant to be the ground snow load, Pg?
If we can use the P flat laod, this will greatly reduce our current demands and thus we want to ensure we are interpreting the section properly. Any other considerations that we need to take wrto Pg at walls to foundation?
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