can i rent a store as a residential apartment in philadelphia?

[Erod R.]

Hi All,

I own a small building in philadelphia, PA which has a small store in the first floor, 2 studios in the second and 2 studios in the third floor.  The building is zone as commercial mix use and it is in a commercial area.  i bought the building in bad condition and hire someone to do the renovation.  at the end of the day, i fired that person because i was not happy with the job he was doing and was stealing money supposedly for the materials.  

This person converted the store into a regular apartment without my permission. he built a regular kitchen (stove, fridge, cabinets etc),  a regular bathroom(shower, toilet ,sink) and added sheet rock to divide the living room and a bedroom.  the store now looks like a regular apartment.  there is no windows in the bedroom and the only windows is in the living room which is the glass windows you see in the stores.  you cannot open and close. there is two doors, one the front door and one door that will lead to the backyard and outside of the building from the back.

please note that i did not change the zoning. it is still zone as commercial property.  my questions is as follow: under the Philadelphia landlord and tenants law, can i rent this so called apartment as a residential apartment?  i am not sure what the laws are but i read online you can use commercial property as residential without changing the zoning but not other way around.  also, i heard that in order to be a legal rental apartment, bedroom has to have windows that can be open and close.

let me know if i can rent the converted store as an apartment without getting in trouble with the law. thanks in advance