Sometime ago I bought an old house that had soft wood floors. Half the house had carpet. The person that had lived there before had cats, and the carpeted area of the house had a strong cat urine smell. The smell was so strong that you would have a gag reflex when you first went in the house.
The solution I hoped at the time was to remove all the carpet, which I did, and this removed most of the smell. To try and remove the rest of the smell I spread baking soda around, and this seemed to work.
However this was at a cooler time of year. When summer came along a slight cat urine smell would come up from the wooden floors. I was never able to get rid of it completely and each summer I would get this problem, albeit it was less pronounced each year.
I was hoping to eventually put new floor coverings on, but for financial reasons I was never able to.
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