How big should I make the opening for him for a homemade enclosed litter box?

[dwdanby]

I have an average size cat. He weighs 10lbs and is at the right weight. I'm building an enclosed area for his litter box. I've got his box inside a deck box, and am cutting an entrance for him in the front of the box. There will also be an opening in the top for a charcoal filter.

How do I know what size the opening for him should be? What would be the smallest size that would still be comfortable for him? Since the goal is odor control, I want the minimum size opening, but still big enough for him to be very comfortable going in and out. Thanks all!

 

[maggie101]

The opening on mine is 10.5 inch wide. Compare it to a litter box

 

[dwdanby]

The opening on mine is 10.5 inch wide. Compare it to a litter box

That's a good idea, and I checked through some boxes listed online. Unfortunately none so far have provided any measurements for the opening or the flap. There does look to be a standard size, they mostly look very similar. I'll start with 10.5 wide, that looks right. Thanks!

 

[maggie101]

As long as he can fit in it. Storage bins are far better than a litter box!

 

[LTS3]

Cats can squeeze themselves into all sorts of tiny places you wouldn't think they would fit into I'd make a litter box entrance at least 12 inches square. To control odors, mix some baking soda into the litter, place odor absorbers near the box, make sure the box location is well ventilated, empty out the box and wash with soap and water monthly or so.