Lou is right about Washington not being in full Masonic regalia when he took the oath of office. I was going on memory when I should have double checked. Washington WAS in full Masonic regalia for a painting he sat for in 1793 or 94, which was during his presidency. It does APPEAR that he was a fairly dedicated Mason. Two links for credible sources (Mount Vernon and the George Washington Masonic National Memorial) back that:

http://www.mountvernon.org/research-collections/digital-encyclopedia/article/freemasonry/

http://www.gwmemorial.org/washingtonTheMason.php

Here's an interesting story from National Geographic that includes an interview with a Masonic historian:
http://news.nationalgeographic.com/news/2009/09/090915-lost-symbol-dan-brown-freemasons-book.html

This has the image of Washington's portrait from 1794 as well as his Masonic correspondence:
http://www.gutenberg.org/files/29949/29949-h/29949-h.htm