building a 'closet' for the litter box
We're getting ready to remodel our laundry room. Our current sink cab (30") is ruined because our big cat sometimes misses his box (pees in the corners and along the sides of the box) and his pee has saturated the particle board sides and bottom of the cab box (stinks!). We were going to put in an sink cab that only had sides and a back, no bottom and open in front - more like a desk than a traditional sink cab - to give him more room and maybe avoid this problem recurring but I kept thinking that was wishful thinking.
And then I hit upon a genius idea, if I say so myself. Install a flap-less kitty door between sink cab and garage and build an insulated closet for his litter box in the garage. We'd add a door large enough to access his litter box for cleaning. The closet will sit above the garage floor on supports (there are 3 steps from garage into house), which makes it even easier to scoop the litter - less bending over, kinder on my back.
But I've no idea how large we should built this kitty closet. I'm hoping someone here can help me.
We're planning on purchasing the large-sized kitty litter pan from Petco - 24" x 18" x 10" walls on 3 sides, shorter wall on one of the 18" wide sides. If we place the pan lengthwise along the wall between garage and laundry room with the the short wall opening near the kitty door, how much room should I leave in front of the box and do you think I need to leave any room around the sides and back? I am hoping that a decent space in front of the box is enough. He's a big cat - 14# (I've never owned anything but large cats. They aren't big when I adopt them but they all grow to be huge).
We're considering covering the floor and sides with peel and stick vinyl tiles or another material that can handle pee but is easily replaced when needed. Also thought about covering the sides with aluminum or SS or something like it that is impervious and can be cleaned with bleach.
I also wonder whether we should add some type of ventilation fan so that the air doesn't stagnate inside the closet. No idea what to choose or how to do this.
Has anyone done something like this before? Any lessons you can share with me? TIA!