Answers: it depends on the contractor..it varies. this is something you should know BEFORE purchasing a home or building a home.
across the world 1 year One year is the standard here in the Tarheel State.
Not sure what you scrounging by "responsible" but I can tell you that a home warranty can change across builders. For example, here in Indiana, my builder be offering a 2 year home warranty. I believe there be only one other builder offering a 2 year warranty, next to everyone else only offering a 1 year warranty.