I am looking to create a structure that will support shade fabric to filter out some of the harsh sun, UV and heat in the desert. The area is approximately 15x26. Although this will be for gardening purposes the advice I seek is related to the structure I'm trying to create.
I'm basically hanging a fabric along the side of my home (the 26 feet length) which I'll connect to the bottom of the terrace porch which has metal posts that I could easily hang my structure from using a medium type of chain. This structure will extend toward the fence which is 15' from the terraced porch of my home.
My plan was to run some type of tubing that will run along the house at the bottom of the terrace (which is 10ft from the ground) and then create 90-degree supports to connect to another tube that will run parallel butted up next to my fence. This tube along the fence will be approximately 8ft from the ground. So basically I want to create a rectangular shaped grid that's 26'x15' and have support tubes running along the 15' width every three feet, more or less. Then I'll drape my shade fabric over this to grow my plants. The fabric isn't heavy at all. This is the item I'm thinking about using:
https://cloudtops.com/product/knitted-shade-cloth-pearl-white-40/
My questions are, other than EMT what other options for tubing do I have that aren't too pricey that will not sag and not rust too fast? I'm hoping to get around 15 or more years out of my project.