Rain on Snow Surcharge

[strguy11]

In ASCE 7-05, is the Rain on Snow Surcharge applied to the Pf, or the minimum Pf?

For a 20 psf ground snow, I=1, the Pf = 14, however the minimum would be 20, depending on the roof type. When applying the surcharge, is it added to 14, or the 20?

 

[haynewp]

It is added to the pf (14+5=20), not the minimum pf (20). But in this case the 20 would still control.