I used the Blackjack 57 in my coop. The stuff has been in there over 6yrs, and looks as good as it did, when it was first laid down. For those reviews that states that it cracks, #1, they probably did not mix/stir it up enough. That's a sure fire way to failure, with the Blackjack. #2, Maybe if the stuff is exposed to all four seasons of weather extremes, on a roof, maybe it would fail after a while. It's not the most expensive roof coat product out there. That's why I bought it in the first place, it's cheap. But it holds up and does a great job under the bedding in a coop. For a coop's wood floor, I don't think you could get a better protector for it, than the Blackjack. Shellac, and paint are not going to work very well, with that waferboard, they are not going to work well, with that rough surface. The Blackjack will totally seal, and stick to it. And there is nothing easier to apply. Just stir well, dump it on the floor and push it around with a paint roller, easy. It will totally seal the floor. Plus the gap, where the floor meets the walls. Moisture, bugs, nothing will get into that sealed gap, once the roofcoat is down.