Roof Live Load for Ag. Buildings under ASCE 7-16

[Travis Roberts]

Hello Everyone,

My question (I think) is about as simple as they come. I am almost positive I remember years back that a Roof Live Load of 10psf was all that was required for an Ag. Bilding

Looking at the ASCE 7-16 I can't find anything other than 20psf for a roof live load.

I'm engineering a 40' 80' light guage steel building in California and the 20psf load is killing me, although I can make it work.

Am I recalling things correctly from long ago, and did they do away with that, or was it never 10psf to begin with?

Most importantly, what Roof Live Load is required to meet the requirements of ASCE 7-16 for an Ag. Building.

(P.S. my tributary area is only 200 sq. ft. so no reduction there.)

Thank you in advance, Travis

 

[1503-44]

I do not recall ever seeing a 10psf live load anywhere.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[driftLimiter]

I know there is a lower roof live load for Greenhouses. Check IBC 1607.13.2.1 (2018).

 

[ChorasDen]

I do not recall ever seeing a 10psf live load anywhere.

Check uninhabited attic space without storage per IBC Table 1607. You'll find 10psf live load there, it's the only place that I am aware of that has such a number.

 

[1503-44]

Every uninhabited attic space I've seen has at least 50 psi of junk stored up there.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Travis Roberts]

Thanks everyone so far.... 1503-44 , driftLimiter, ChorasDen ..... I appreciate the time. I ended up designing for 20psf Roof Live Load.

 

[Travis Roberts]

For what it's worth, I did find where I had seen the 10 psf load.... the 1991 UBC..... the code in effect when I graduated college, lol. I am hopefully uploading the table from that code to show I wasn't crazy

 

[1503-44]

Interesting. I was designing prefab roof trusses in the 70s. I did a rodeo arena roof once. Not an ag building, but as close as I ever got.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."