Enlarging a Backyard Window

I am trying to figure out whether I need to apply for a permit (DOB or Landmarks or both) for enlarging a window that faces my backyard in my single-family home. It’s a landmarked building in a historic neighborhood in Clinton Hill. The window will be enlarged from 2 ft by 3 ft to 6 ft by 6 ft. Thoughts?

By matter445 |