From our house

When a cat starts peeing outside the box, the box is only half the story; the other half is a bladder that may hurt. This chapter covers the setup that keeps a cat using the box, the conditions behind most urinary trouble, and the one true emergency, a blocked male cat, that you need to recognise in seconds.

We have three cats in an apartment: Zorro, an orange tabby, neutered, three years old; Dina, a tabby, spayed, also three; and MJ, their fluffy white daughter, spayed, two. For litter we run one PetSnowy automatic box and one plain backup tray, both filled with Dr. Elsey's Cat Attract, a clumping clay. That is two boxes for three cats. We will come back to that number, because the guideline is not kind to it.

Autumn 2026 was Zorro's hard season. Among everything else that went on with him, and Chapter 1 tells that story in full, he started peeing around the house. Whether he was leaving puddles on the floor or marks up the walls is a detail we did not think to record at the time, and it matters more than we knew. If the marks were vertical, that is marking, and it belongs with the rest of his stress story in Chapter 1. If they were puddles, it belongs here.

What we did right, mostly by luck, was go to the vet before we went to the internet. Our vet ran a blood panel. On 21 October 2026 the results came back entirely normal, with nothing of concern. We felt relief and then, about ten minutes later, frustration, because normal results tell you what it is not. It is not his kidneys, not his thyroid, not diabetes. That left the box, the household and his head, which is the order the guidelines say to work through, and the order we tell it in this chapter.

About the box count. The guideline is one box per cat plus one, which for us is four.¹²³⁴ We have two. We cannot prove the count had anything to do with Zorro's autumn, and we cannot prove it did not. We tell you our setup as what we do, not as what you should do. PetSnowy is a paid partner of ours, so you should also know that nothing in this chapter is a recommendation of their box or anyone else's. The evidence on automatic boxes is a blank, and we say so below.