That's down to lax caretaking, and yes I've smelt it too. But my house has not a whiff of anything untoward, unless winds force air down the chimney and you can

That's down to lax caretaking, and yes I've smelt it too. But my house has not a whiff of anything untoward, unless winds force air down the chimney and you can smell a bit of smoke. You will never smell anything cat-related (and yes there's a cat).