I would think you should tip your awning down as far as it can go. Then measure the height of end of the awning to the ground. That should be the height of your shade. Any longer, and if you tip it, it will be on the ground.
We considered getting one many years ago, but opted instead to get a Quick Shade. We purchased this one in 1999 and used it with our pop-up. Unfortunately, 2 weeks ago, the cover finally gave way and ripped in two. But it sure did last a long time. The nice thing about the collapsible, accordion-scissor style canopies is the fact you can move them anywhere, tilt them to maximize the shade, and even use them when not camping (for example going to grandma's for a cook-out and you need a bit of shade, in her back yard, at the park, at the beach, or anywhere!)
Like I said, the red one, almost 17 years old now, finally died. We checked it at the last campground trash container. Then went out to "****s" (D i c k's ... RV.net editor going crazy again)... sporting good and decided to buy a new one. The old was 10 x 10. We really wanted a 12 x 12, but when we saw how huge it is (set up in the store), we realized the 10 x 10 was more practical. We ended up, actually, getting 2 of them. The cost of 2 of the 10 x 10 's was cheaper than the single 12 x 12. Plus with 2 of them, we have all kinds of configuration possibilities.
Just a little luck, but when both of the shades are together, they match up to the camper awning perfect. Together, they are only about 1 foot shorter than my awning. So the 10 foot awning shade space, can now become 20 foot x 21 foot! Plus, the shades tilt, by simply lowering 2 legs on 1 side, blocking the sun, but allowing us to see under it.
Here's a photo, first time we used the new ones last week-end. I originally had them against the trailer awning, but the morning sun came up, so decided to reconfigure! Worked REAL nice!
This is a nice alternative.... and gives you more versatility! Something to think about!
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