Beams Supporting purlin braces

[Durant]

No plans, so how do I determine beam sizing for supporting purlin braces in attics? Spans usually 16 to 24 feet. Is there a chart?

Durant

 

[jeffc]

Here are the tables i started with back in the day: http://www.awc.org/pdf/wsdd/c2b.pdf These charts only work uniformly distributed loads.

You would need to know the snow load for your area to determine the W (total load including deadload), the numerical value that corresponds to the grade for a given species (Fb, Fv and E). These charts take time to figure out get but easier with use. They have similar charts for manufactured wood products.

 

[Durant]

Jeffc,

Because of the spans of 16 ft. and more; I was looking for the manufactured wood span charts for LVLs, etc. for beams supporting purlin braces in attics.

Thanks,

Durant

 

[Sifu]

I ask for the Mfr. to provide individual member reports for LVL's. I will then verify the loads, locations, supports and sizes as shown on that report. Some AHJ's want those reports to be sealed.

 

[dhengr]

Durant:

What is a beam supporting purlin braces in an attic? If you are using manufactured wood products you want to use the load tables from that manuf’er. because there are minor variations in the products and processes which affect the mechanical section properties and the allowable stresses for each manuf’er. Ask your lumber yard for load tables and catalogs for the products they sell. They will only have a couple suppliers for these products, and you have to use the right tables and catalog details.

 

[ICE]

Have you considered asking an engineer?

 

[dhengr]

Thanks ICE, I’ll do that..... He seems to have the exact same question.