You can buy 10' galvanized pipes (that match the ones in the run) and also buy brackets designed to attach the pipes in a T shaped joint. The 10 footers will go across the shorter 10' dimension of the dog run. The brackets allow you to run one pipe into another pipe at a right angle without welding or drilling, quickly creating a T joint. Once those pipes run across the top, you could attach nearly anything to the new "rafters" you just installed -- even solid panels of whatever material you like could be attached by drilling into the new poles crossing the expanse of the coop. Be sure to use washers (waterproof variety to keep it from dripping in the rain) and bolts to hold it down securely.
Then, use the tarps along the sides, attaching them with zip ties or carabiners.
If the tarps you place along the sides billow and snap and pop too much in the wind, causing them to tear away or just make too much noise, you might choose to run some kind of cord or other material from side to side, spacing it at intervals up the side of the tarped wall, trapping the tarp against the chain link walls. Or drill holes into plywood sheets and bolt it on to the frame of the kennel walls.
We used those galvanized pipe across the top of our dog-kennel-turned-into-chicken-coop and are really glad we did.
We need to keep predators from going over the top of the run, as it backs up to a tall concrete block wall, and they can get on the wall and drop into the run. So we bought hog panel fencing from
Tractor Supply (the one with smaller holes dia approx 3"x6"), cut it in pieces to fit, placed them on the roof resting on the newly installed cross pipes and zip tied the hog panel to the top of the walls and the cross poles, which now act effectively as rafters. This provides a very strong barrier against predators, even birds, being able to go over the top.
We bought 80% shade cloth (Tarps PLus or
Amazon) and using zip ties, we strapped the shade cloth via the grommets along all 4 sides of the shade cloth, around the 4 sides of the perimeter, on the top of the run. Although the rain gets thru the tarp, it doesn't pour down on top of them, pelting them with big rain drops. We have an elevated hen house with perches underneath, so they can stand under it or go inside when its really wet -- which doesn't happen much around here.
But then, one day we needed more shade so we draped tarps over the top of all the other stuff and using bungee cords, pulled downward, we attached the tarp to the chain link walls with the bungee cords, like you did. We used a tarp that only gave us a 1 foot overhang. We would use one bungee strap for every two grommets by threading the strap through the chain link from one grommet to the next, placing the strap far enough below the edge of the tarp to pull it tight and reduce the amount of give on the bungee cords (but not too tight because the top edge of the chainlink can rub and poke holes into the tarp in places. ) That also placed the bungee cords up high out of our way. Possibly, the "rafters" we installed also limited the tarps from snapping as much and that helps keep the in place. Anyhow, it's worked for us so far and we have managed to hold down the tarp and it stays down even in the strong Texas winds.
Good luck and best wishes for an easy solution!
