The movie star, who moved to New Orleans shortly after the horror of Hurricane Katrina in 2005, was so appalled by the devastation he saw all around him in the city, he set up the Make it Right foundation and began persuading his architect friends to get involved in helping the homeless.
Five years later, he's getting closer to realising his dream of building 150 homes, which will withstand another fierce storm and keep the costs down for struggling families - and even he can't believe how well the job is going.
Speaking to U.S. newsman Brian Williams as part of a new TV documentary to mark the fifth anniversary of Hurricane Katrina, Pitt says, "These homes are elevated above Katrina flood waters, they are stronger; they'll take a category four (hurricane)... so none of these homeowners will suffer those horrors (of Katrina).
"Last month, these homes, every one of them but one was producing more energy than they were eating; that's an amazing story."
And the actor hopes his efforts and those of the eco-architects he's working with will provide a template for those building houses for struggling families: "There's no reason now to build any other way."