cat urine odor in closet walls?

[llsrvd]

I have a closet that seems to smell of urine.  It's not just on the floor or at cat height but all the way up the walls.  I don't think any of my cats peed in here.  The closet has always smelled funky since we moved here.  Is it possible for cat urine smell to infuse dry wall well out of cat-spray reach?  For example if a previous owner kept a litter box in here?  What could I use on the dry wall to get the odor out?

 

[howmany]

Is this a house you own ? I ask because I wonder how far you want to go? You could rip up any carpet pull off the drywall and seal the subfloors replace the dry wall and paint!
Is it a flat could it becoming from above?
Using a good cleaner for pet urine and then a sealer like Bins paint could help . Also is it damp you could run dehumidifier in it after clean but before sealing .

 

[Willowy]

Mold frequently smells like cat pee. I'd have it checked out by some sort of professional (are there mold professionals? Lol).

 

[grrr cat]

Have you check the closet with a black light ? see if you can see any urine spots glow in the dark?

 

[llsrvd]

I'm new here so wasn't quite sure how to reply to all 3 answers at once.  Thank you all!  I have been wondering about mold.  The closet is on the North side of the house which never has sun beating on it.  So I fear ripping out the drywall may be the answer.  I think I will get a black light to check for urine just in case.  

 

[howmany]

Yes there are mold professional [emoji]128512[/emoji]We lived in an old upper flat before moving to the country and we had moldy windows and under sinks no one had bothered to fix or seal properly . They can check air levels.