Sun Shade Question

I am about to start building a greenhouse and I plan to cover the top with a sun shade during the summer. Is there a concern about any movement of the sun shade over the clear canopy? How tight do you pull down on the sun shade to stop movement? My thinking is that movement would dull and scuff the polycarbonate or is this not a problem?

I was waiting for someone else to answer since I really don't have any experience with this. I have never heard anyone mention that this was an issue though. Hopefully someone will pop on and let us know soon!

Our shade cloth is stretched tight and anchored securely. I don't think the problem is scratching the surface but the loss of the shade cloth in high winds. I should also say I don't have roof vents so tight is not a problem.

Brooke

I could not find any discussion anywhere on this possible problem so maybe it just has not been a concern.
Thanks Oldude

I also think that the biggest concern is blowing away in the wind, I don't think the shade could scratch the polycarbonate enough for it to be a problem. But believe me that the wind will get a hold of any little loose piece of anything on the greenhouse, and as it rips the shade off, that might damage the greenhouse. So I'd put it on tight to avoid that.