I really did think they would chew it, but they haven't. My goats don't chew at all... I just used some rubber-like stuff from lowes, I bought a few feet. It was really cheap and has done a great job so far.
I did the same thing on my goat shed. It does really help keep the wind and snow out. I didn't cut any strips in my though. The goats just push on it and in they go. My goats must be angels too, they don't chew on it either. But mine will steal $ 5.00 out of your pockets and eat that. Go figure.
I was in Lowes and Home Depot this past weekend and couldn't find anything that looked like the material you used for your door flap . . . if you could provide any more details, that would be wonderful! (i.e. was it on a roll and you had it cut, was it in the flooring section, etc.).
My husband runs an excavation and landscaping supply company and probably about two years ago he brought some rubber "pond liner" home- and thats exactly what we did with it! We hung it over the small doors- and even a 10x10 run in, it really makes a huge difference.
We kept ours in solid flaps sort of like a regular dog door- it only takes them about 5 minutes to figure out they can push it open and come and go.
Thanks PHF. We recently built a little run-in on to the back of an existing structure. We made it taller than our other run-in to make it easier for us to get in to clean, add minerals, etc. However, with the cold snap we had last week, I quickly realized how much colder it was than our more-enclosed run in. I am hoping that this will be a good solution during the winter months, provided they don't decide it's tasty.