Roof Loads for a Pre-engineered bldg

[SKJ25POL]

May I ask if anyone knows what are typical values for Roof Live Load, Roof Dead Load and Roof Collateral Load for a pre-engineered bld?
Any source or code that these numbers come from?

Thank you

 

[ztengguy]

From where i am at, its about 8-10 psf dl, and about 20 psf ll. It all depends on the spec for the roofing type, additional dead load. the live load is usually snow load, or min live load.

Check IBC

 

[JAE]

In what country, location is the project?



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[SKJ25POL]

JAE (Structural),
It's located in US.

 

[hawkaz]

Depending on your region, DL could be as low as 3 psf, LL could be 20 psf (reducible) and collateral load is up to the owner based on their needs.
LL is code based. The rest is project specific.

 

[dmoench01]

Hawfaz is correct about DL and LL. The loading for these buildings is no different than a conventional steel building. They are just have lighter framing but the same environmental loads.

 

[SKJ25POL]

hawkaz (Structural),
Thank you for your reply I guess it was clear and straigthforward answer.
Thanks

 

[XR250]

Metal buildings are typically designed to be as cheap as humanly possible. The manufacturers will, unless told to do otherwise by the EOR, will design them for actual roof dead loads with no collateral load and L/90 for wall framing. I even had one recently where they designed it for a 12 psf roof live load and specified special scaffolding was required for workers on the roof.
So be careful when specifying them.