Also, for the smell of the feces and urine you may want to consider "NATURES MIRACLE". It is a product sold at petsmart and petco. You can also find it online cheaper but it works on a enzyme level to biodegrade urine and feces odors in dogs and cats. I would think it can be very effective with rats that are much smaller animals. And the benefit of knowing it's just not a perfume to mask the odors. Probably use it to initially wipe out the cement mixer prior to the pine pellets and the bedding being laid. It might help. :)