Visitors to the historic mountain villages in central Japan marvel at the elegance of the steep thatched-roof farmhouses found there. Known as “gassho-zukuri,” Japanese for “constructed like hands in prayer,” the architectural style emerged more than 250 years ago to ruggedly withstand the area’s heavy winter snowfalls. Recently, a National Institute of Standards and Technology (NIST) fire researcher and his Japanese colleague conducted a special fire test to learn how to protect these treasured icons, and other thatched-roof structures around the world, from a more insidious threat: fire.