Pro - Does anyone else's nest boxes get soaked in rain?

[Chickabee]

Has anyone else used these for their covered runs? I originally had them for my rabbit, sadly she died and I had a big bag left. I use it in the runs that aren't on slabs. You get a bucket full and throw it in, you could mix it with biodry or similar. Once the girls have scratched around in it, it turns into highly absorbent powder like straw, but not dusty. It absorbs smells too. It was great for the rabbit. At first it looks lumpy and uncomfy, but it's highly absorbent and soon breaks down. I think you can probably compost it too