after watching the UoG videos on youtube, I bought a couple of yards of heavy canvas to use for inner covers on some new hives that i hope to fill this spring. I also read Charles Dadant's book "The Dadant System of Beekeeping", where they used (100 years ago), oilcloth for inner covers. the slick side i'm guessing went down ?, so that it would easily peel off of the top of the frames? i plan of trying a few oilcloth inner covers as well. (i believe that quite often, "the old school is the best school"). has anyone else tried oilcloth?
I am using feed sacks. They unfortunately lack an UV inhibitor. You get a couples of years use and they disintegrate. I would try barn curtain material if I had some that was new. This is a heavier material that does contain a UV inhibitor. It is used as a roll up curtain on poultry houses, for hogs and dairy barns. I get about 10 years service from it even when exposed.
Talking of old, I think abby warre used burlap but he put a flower paste on it first.
One source online for 18 oz Canvas/Duck Cloth is Sailrite ...
They don't kill you on shipping. I picked up some to try.