What is the widest I can span a gambrel barn?

Asked by Kim Petersen from Winnemucca, NV

What is the widest I can span a gambrel barn?

I am looking to build a post and beam wooden barn to use for weddings and special events. I want to be ready to build early spring.

I am from Winnemucca, Nevada so good temper beams are hard to come by.

Is there a way to purchase a kit with materials?

I am also considering a wood floor to dress it up from concrete. I am hoping to find a way to insulate it so I can use it in the winter. Thanks for your help.