Have you asked if they intend to keep the barn doors closed after the repair? I have been called to a job simular to this. I asked the farmer if they ever close the main doors and he said no. Since they were not going to keep the doors closed, fixing the rafter opennigs was a non-issue.

I figured thats what GAW meant but wasn't positive. They sell it at Ace hardware. Yes she does intend for the barn to stay closed up most of the time.

Pesky, dont worry. Any advice I get I take! Especially when it comes to safety. So wearing my mask with dust filters would be a good idea?