"Chuck" wrote in message
news:H8u7c.48396$Zp.2100@fed1read07...

I'll be building a carport in the near future. I would like to make my own
frame to support the roofing panels. The span between the posts will be 20
feet. I'm thinking that some 2x4x.120 rectangle tube should be strong
enough
for the horizontal, but what I need to know is will the tube sag under
it's
own weight . Has anybody had any experience with this kind of framework
before, or is there some place you could direct me to find some answers?

Many Thanks,

Chuck in Phoenix



I-beam would be better, it would put the most metal where it's stressed the
most. I wouldn't want to go dancing in the middle of _any_ 20 foot beam
that's only four inches deep, though (it would give a new meaning to the
word "springtime"). Surely there's a building code for your area that would
cover this?

Why not use wood, or manufactured wooden I-beams?