Can a loft space with no door be considered a bedroom?

[Jeremy Burnheimer]

Basically what the title says. My unit has a finished third floor in the attic, however, there is no door to this floor. The space is big enough for a bed, has a window, etc. 

Side note, when they were selling the house they considered this space the 3rd bedroom, but during the appraisal, they considered it a loft.