I believe there has been a fence around the White House for many years, including when 0bama lived there (barf).
Remember when baraq blocked off Pennsylvania avenue with concrete barricades?
I believe Obama raised the fence AND added other security features which was under construction fore a very long time.
It was made 5 ft hire under a proposal made during the Obama administration. IIRC, it was closed to visitors while other security items were being built.