Here is my netting sagging low after an ice storm. Yet it didn't tear, and it bounced back to original height after the ice melted. 2nd pic is a close-up:
This a a 25' expanse, held only by zip ties on cattle panels at each side.
I have had bird netting stretched over my run for 4 years, and it has held up to snow, ice, even small branches falling on it and my cat walking on it. It is not sloped, it kind of sags. At the widest, it's stretched 25' and is attached to 5' high cattle panels with zip ties. With a heavy load...