How can I tell if....

[Milehighxr]

The "beams" that my ceiling skin is attached to(plywood in my case, not drywall) are structural or not. There is a section of my garage that I know was an addition to the original, and it does not have roof trusses. All it has are 2x4x20 and then the roof beams for the roof deck(I hope I'm clearer than mud). What I want to do is remove the ceiling, and the 2x4x20s that it is screwed to, to increase the height in that area. I'll redo all the insulation and even add some bracing to the roof beams. I'll take photos of the area in question later if what I am proposing isn't clear(wed earliest).

I want to do this because, I have just recently acquired a 2x8x10 industrial rack, and I really don't want to cut it shorter. I also want to hang light weight items like a canoe(it's kevlar so it should be about 40lbs or less) from the ceiling while still having room for my taller friends/family to move without them walking on their knees...

 

[p_mori7]

We need pictures.

 

[Milehighxr]

I lied they're 2x6x20, pics:

This is what is above the original 20x20 garage, typical truss that you would normally find.



This is the are over the 10x20 addition to the garage. There is only one 2x6x10+ that runs diagonally from the end of the wall, to the original roof area. other than that it is wide open. If I can open this up, (even only part of it) it will give me a lot more space for shelves.

 

[Steevo]

Better.
Now you are clear as mud . . . .