Keeping the house dry and Ventilated are essential. Those are met by my house design. Twice daily I clean the litter bin under the roost and removed material goes to a leaf/litter compost pile. I then spritz the bin and soiled areas with bleach, toss in a small amount of fragrant cat litter and cover with fresh pine shavings. Keeping odor down is important as the fence between my and my neighbor's yards is only 10 feet away. Chickens are not in the house during cleaning except those laying. They free-range in the afternoon, so no exposure to chemical odors which disappear fairly quickly. And no, pure bleach spritzed in small amounts will not hurt anything and will keep down odors, salmonella and other microbial pests. It even works for mites by spraying their day-time hiding places( cracks, joints, dark places, floor openings, etc) - more frequently in warm weather. Never once have had a complaint from neighbors, birds are healthy and laying well, & I have cleanings down to 10 minutes each time. It takes longer to water & feed than to clean since only a day's amount is put out to control waste and cost. Feed has gone up 30% or more in the last few months so waste is not allowed.