Older Siamese feller (15 yrs with cardiomyopathy) has been a very good litter box user. He's the dominant of the two cats and has rarely covered his poop in the box but always the pee.
We moved from a condo in California with wall-to-wall carpets to an apartment in Florida (also fully carpeted) and litter box habits began to deteriorate a little ... Took him to a vet who thought arthritis might be making it uncomfortable for him to get into the box, so perscribed Adequan. I put puppy pads around the litter box for extra protection and every now and then one would get soiled.
Then we moved to a house with tile floors. Within about 3 months he started peeing on the guest bathroom floor (tile). I put a small litter box in there and all was well. Both cats seem to use it when the mood strikes.
Then last year, the old guy started "missing" the main litter box. Fine with poops, not so with pee ... I have been using Worlds Best Litter for the last many years, so no change there. Anyway, slowly the litter pads seem to get used more and more ... I started a litter change last month to Blue Buffalo clumping and now it's nearly a daily occurrance to have to change at least one of the puppy pads around the litter box.
Last night, right after I cleaned the litter box (including recently deposited poop), and sat down at my desk, he squatted on a felt saddle pad I leave on the floor for them to sleep on ... and peed on it. I'm pretty sure it's a goner, even tho I tried to shower it off right away (it's a non-wash thing).
Someone suggested that he may not like the feeling of peeing in litter any more and has become accustomed to the pads.
I can change puppy pads for the next however-many-years it takes, but I'm a bit concerned that he'll widen his swath, so to speak, and I'll end up with the entire house covered in 'em.