cat box

I agree in that you might want to change the litterboxes more frequently. Also, maybe the brand of litter you use is not working well. I use a brand called The World's Best Cat Litter. I like it because is is made of corn that cannot harm my cat. It seems to keep the odor at bay as well.

i have 5 also-i rinse out their boxes frequently,and put a bit of baking soda in the bottom before i add the fresh litter.there is also a "stick-up" air freshener above the box. four of mine are males,and usually they have stronger urine,but it's really not bad at all with the baking soda.

If they are using the litter box only, and no area in the house, then switch gradually to pine litter. You will never ever smell urine. It is bio degradable. But, you must mix it to ease them into it. They are small pellets of natural pine. I have two cats, and never do you smell urine in this house. The tracking of litter is cut 90% down too. Good luck. Please give it a try.

Maybe the litter trays need to be cleaned more regularly, or maybe try another style of litter..

Im assuming there is a window in the room, try installing an exhaust fan, their about $40 and blow the air outside.

Are you sure they are really doing their things in their boxes? Here at home we had to buy some kind of repellent because the cat sometimes didn't wanted to bother to go to the box and urinated in some furniture, After we applied that product it didn't happen again. I think she learnt a lesson.

I found that chumping litter helped keep our litter boxes fresher. But considering that you said that you have tried different types of litter, I presume that you have already tried that. Personally, I would aviod scrubbing down the cat boxes with bleach. One, it is not good for kitties. And two, I find that it reacts badly with cat urine--it reminds me of mixing certain cleaning supplies together; call it chemical warfare.