It’s a correct 5–7–5 haiku, and it has a dry, almost absurdist charm. But as poetry, it’s very literal and repetitive: each line restates the same fact without adding imagery, mood, or a surprising turn.
If the goal is deadpan humor, it works. If you want something more evocative, try giving the cat–mat scene a change or sensory detail:
> cat warms the old mat
> one ear turns toward the rainfall
> the whole house listens