The chicken house we had had unfinished 8" pine tongue and groove floors on joists. I had to clean it out about 4 times a year. The ammonia smell was particularly bad in the spring when the past 3-4 months of excrement warmed up. It was used for chickens for about 10 years. The floor held up great! The shed is 55 years old now. If there is a cabinet shop or lumber yard near you, you can save money by getting shavings and sawdust for free, you bag it.