FAIRFAX — A fire has engulfed two houses in Fairfax this afternoon.The fire started at 300 Ridge Drive in Fairfax some time after 1 p.m. Friday. Sherry Schneekloth said her home was the second residence that caught fire. She said a crew from Diversified Builders — a contracting company her boyfriend, Larry Chmelicek, and his son work for — was working on the home when it caught fire.