"Based on the numbers that engineers use when designing, the average weight of a commercial 2x4 is 1.28 lbs per foot... A 2x2 weighs 0.64...
I'm using .065 wall 1x1 steel tube, that weighs .827 lbs per foot...
So, it's considerably less weight that a 2x4 and a little heavier than a 2x2..."
That information is from
The Dirtybus...