i dont have any ventilation going outside in my shed. I keep the door open when Im cleaning the racks and I have a fan blowing threw the racks at all times. I also have ac hooked up to the building but so far it hasnt really gotten hot enough for me to use it the only time I cut it on is when im in there cleaning. The poop doesnt really effect me but the urine smell is very strong. I clean the racks once a week on the weekends