Drift Load + Unbalanced ?
Drift Load + Unbalanced ?
(OP)
I have a 12:12 gable roof addition adjacent to a 62' vertical wall. The gable roof will receive a drift load.
ps + pd = 30 + 74 = 104 PSF. <<<--- This does NOT include unbalanced snow load prior to adding the drift.
I do not see in ASCE 7-05 (our state's current reference) if drift should be added to unbalanced or if the drift could (reasonably) cancel or omit the unbalanced.
In the past, I've never included the unbalanced in such a situation.
In the pre-IBC past, 90 PSF drift (for this region) was typically the max drift ever used - with this firm.
Suggestions?
Thank you!
ps + pd = 30 + 74 = 104 PSF. <<<--- This does NOT include unbalanced snow load prior to adding the drift.
I do not see in ASCE 7-05 (our state's current reference) if drift should be added to unbalanced or if the drift could (reasonably) cancel or omit the unbalanced.
In the past, I've never included the unbalanced in such a situation.
In the pre-IBC past, 90 PSF drift (for this region) was typically the max drift ever used - with this firm.
Suggestions?
Thank you!






RE: Drift Load + Unbalanced ?
RE: Drift Load + Unbalanced ?
RE: Drift Load + Unbalanced ?
My inquiry was intended to discover if ASCE implied, anywhere, that i could not see, that drift should be superimposed on unbalanced. I simply want to avoid the potential that a few of the respectfully analytical state plan reviewers may decide that the drift need be imposed to unbalanced, thus, requiring me to recalc the entire project.
Bala0404, you state that you apply the conservative drift + unbalanced. However, according to your attachment, (which is beneficial - thank you!), the applicable calculation for Area C1 implies only drift + balanced.
Thank you both for your input.
RE: Drift Load + Unbalanced ?
Jim