I want to add a second floor to my garage, which is made of cinder
block 21 x 22 feet. I am very new at woodwork and my English is pretty
poor. So please be patient with me. I need some input about my design
for the second floor, which will be used as storage, not a living
space. The garage is by itself, completely separated from the house.
I am planning to have an engineered center beam that span 21 feet and
will support all the 2x8" 11' joints 16" oc. The second floor
will be 8' at the center and 6' on each side with 2x6" 12'
rafters 16"oc. These rafters will be supported at the center by a
4x8 solid ridge that spans 21 feet. The framing will be made of 2x4
16"oc. One of my concerns is about lateral support for the side
frame.

Thanks.

Claudio Robles